diff --git a/.github/workflows/mypy.yaml b/.github/workflows/mypy.yaml
index 089c7d18ad6f2..a19be8525f902 100644
--- a/.github/workflows/mypy.yaml
+++ b/.github/workflows/mypy.yaml
@@ -43,8 +43,8 @@ jobs:
         mypy vllm/worker --config-file pyproject.toml
         mypy vllm/spec_decode --config-file pyproject.toml
         mypy vllm/lora --config-file pyproject.toml
+        mypy vllm/model_executor  --config-file pyproject.toml
 
         # TODO(sang): Fix nested dir
-        mypy vllm/model_executor/*.py  --config-file pyproject.toml
         mypy vllm/core/*.py --follow-imports=skip --config-file pyproject.toml
 
diff --git a/format.sh b/format.sh
index 4ac1842daef0a..bd12e61d77806 100755
--- a/format.sh
+++ b/format.sh
@@ -105,7 +105,7 @@ mypy vllm/transformers_utils --config-file pyproject.toml
 mypy vllm/engine  --config-file pyproject.toml
 mypy vllm/worker --config-file pyproject.toml
 mypy vllm/spec_decode --config-file pyproject.toml
-mypy vllm/model_executor/*.py  --config-file pyproject.toml
+mypy vllm/model_executor  --config-file pyproject.toml
 mypy vllm/lora --config-file pyproject.toml
 
 
diff --git a/vllm/model_executor/guided_decoding/lm_format_enforcer_decoding.py b/vllm/model_executor/guided_decoding/lm_format_enforcer_decoding.py
index 0d74a5f8e81ff..d0a5ca5592f9d 100644
--- a/vllm/model_executor/guided_decoding/lm_format_enforcer_decoding.py
+++ b/vllm/model_executor/guided_decoding/lm_format_enforcer_decoding.py
@@ -61,6 +61,7 @@ def _normalize_json_schema_object(schema: Union[str, dict, BaseModel]) -> dict:
         return schema
     if isinstance(schema, BaseModel):
         return schema.model_json_schema()
+    raise AssertionError(f"Unsupported schema type {schema}")
 
 
 @lru_cache
diff --git a/vllm/model_executor/layers/linear.py b/vllm/model_executor/layers/linear.py
index 1bd6c42ab3fd8..4d43ed4c5f14a 100644
--- a/vllm/model_executor/layers/linear.py
+++ b/vllm/model_executor/layers/linear.py
@@ -128,7 +128,8 @@ def __init__(
             params_dtype = torch.get_default_dtype()
         self.params_dtype = params_dtype
         if quant_config is None:
-            self.quant_method = UnquantizedLinearMethod()
+            self.quant_method: Optional[
+                QuantizeMethodBase] = UnquantizedLinearMethod()
         else:
             self.quant_method = quant_config.get_quant_method(self)
 
@@ -160,6 +161,8 @@ def __init__(
         super().__init__(input_size, output_size, skip_bias_add, params_dtype,
                          quant_config)
 
+        # All the linear layer supports quant method.
+        assert self.quant_method is not None
         self.quant_method.create_weights(self, self.input_size,
                                          [self.output_size], self.input_size,
                                          self.output_size, self.params_dtype)
@@ -173,6 +176,7 @@ def __init__(
 
     def forward(self, x: torch.Tensor) -> torch.Tensor:
         bias = self.bias if not self.skip_bias_add else None
+        assert self.quant_method is not None
         output = self.quant_method.apply(self, x, bias)
         output_bias = self.bias if self.skip_bias_add else None
         return output, output_bias
@@ -221,6 +225,8 @@ def __init__(
         self.output_size_per_partition = divide(output_size, tp_size)
         if output_sizes is None:
             output_sizes = [output_size]
+        # All the linear layer supports quant method.
+        assert self.quant_method is not None
         self.quant_method.create_weights(self,
                                          self.input_size,
                                          [x // tp_size for x in output_sizes],
@@ -255,6 +261,7 @@ def forward(self, input_):
         bias = self.bias if not self.skip_bias_add else None
 
         # Matrix multiply.
+        assert self.quant_method is not None
         output_parallel = self.quant_method.apply(self, input_, bias)
         if self.gather_output:
             # All-gather across the partitions.
@@ -579,6 +586,8 @@ def __init__(
         # Divide the weight matrix along the last dimension.
         self.tp_size = get_tensor_model_parallel_world_size()
         self.input_size_per_partition = divide(input_size, self.tp_size)
+        # All the linear layer supports quant method.
+        assert self.quant_method is not None
         self.quant_method.create_weights(self,
                                          self.input_size_per_partition,
                                          [self.output_size],
@@ -624,6 +633,7 @@ def forward(self, input_):
             input_parallel = splitted_input[tp_rank].contiguous()
 
         # Matrix multiply.
+        assert self.quant_method is not None
         output_parallel = self.quant_method.apply(self, input_parallel)
         if self.reduce_results and self.tp_size > 1:
             output_ = tensor_model_parallel_all_reduce(output_parallel)
diff --git a/vllm/model_executor/layers/quantization/__init__.py b/vllm/model_executor/layers/quantization/__init__.py
index 0820f17c5c50d..70e0a7cfe3e3b 100644
--- a/vllm/model_executor/layers/quantization/__init__.py
+++ b/vllm/model_executor/layers/quantization/__init__.py
@@ -1,4 +1,4 @@
-from typing import Type
+from typing import Dict, Type
 
 from vllm.model_executor.layers.quantization.aqlm import AQLMConfig
 from vllm.model_executor.layers.quantization.awq import AWQConfig
@@ -9,7 +9,7 @@
 from vllm.model_executor.layers.quantization.marlin import MarlinConfig
 from vllm.model_executor.layers.quantization.squeezellm import SqueezeLLMConfig
 
-QUANTIZATION_METHODS = {
+QUANTIZATION_METHODS: Dict[str, Type[QuantizationConfig]] = {
     "aqlm": AQLMConfig,
     "awq": AWQConfig,
     "fp8": Fp8Config,
diff --git a/vllm/model_executor/layers/quantization/base_config.py b/vllm/model_executor/layers/quantization/base_config.py
index b755b1328504a..ff5cf0b2bd61a 100644
--- a/vllm/model_executor/layers/quantization/base_config.py
+++ b/vllm/model_executor/layers/quantization/base_config.py
@@ -1,5 +1,5 @@
 from abc import ABC, abstractmethod
-from typing import Any, Dict, List
+from typing import Any, Dict, List, Optional
 
 import torch
 from torch import nn
@@ -76,8 +76,16 @@ def get_from_keys(config: Dict[str, Any], keys: List[str]) -> Any:
                          "quantization config.")
 
     @abstractmethod
-    def get_quant_method(self, layer: torch.nn.Module) -> QuantizeMethodBase:
-        """Get the quantize method to use for the quantized layer."""
+    def get_quant_method(
+            self, layer: torch.nn.Module) -> Optional[QuantizeMethodBase]:
+        """Get the quantize method to use for the quantized layer.
+        
+        Args:
+            layer: The layer for the quant method.
+        Returns:
+            The quantize method. None if the given layer doesn't support quant
+            method.
+        """
         raise NotImplementedError
 
     @abstractmethod
diff --git a/vllm/model_executor/layers/quantization/squeezellm.py b/vllm/model_executor/layers/quantization/squeezellm.py
index 971078fe25a9b..207dbcee8afc5 100644
--- a/vllm/model_executor/layers/quantization/squeezellm.py
+++ b/vllm/model_executor/layers/quantization/squeezellm.py
@@ -52,11 +52,10 @@ def from_config(cls, config: Dict[str, Any]) -> "SqueezeLLMConfig":
         return cls(weight_bits)
 
     def get_quant_method(
-            self,
-            layer: torch.nn.Module) -> Optional["SqueezeLLMLinearMethod"]:
+            self, layer: torch.nn.Module) -> Optional[QuantizeMethodBase]:
         if isinstance(layer, LinearBase):
             return SqueezeLLMLinearMethod(self)
-        return
+        return None
 
     def get_scaled_act_names(self) -> List[str]:
         return []
diff --git a/vllm/model_executor/layers/rotary_embedding.py b/vllm/model_executor/layers/rotary_embedding.py
index b8361af61ae3f..25365a9b50a1f 100644
--- a/vllm/model_executor/layers/rotary_embedding.py
+++ b/vllm/model_executor/layers/rotary_embedding.py
@@ -431,8 +431,8 @@ def forward(
                               torch.full_like(positions, k)).long()
         idx = (torch.add(positions, long_prompt_offset)
                if long_prompt_offset is not None else positions)
-        self.long_short_cos_sin_cache = self.long_short_cos_sin_cache.to(
-            idx.device)
+        self.long_short_cos_sin_cache: torch.Tensor = (
+            self.long_short_cos_sin_cache.to(idx.device))
         idx = torch.add(idx, offsets) if offsets is not None else idx
         cos_sin = torch.index_select(self.long_short_cos_sin_cache, 0, idx)
 
diff --git a/vllm/model_executor/layers/sampler.py b/vllm/model_executor/layers/sampler.py
index 4ef25edecfd24..d79c99e5d0a45 100644
--- a/vllm/model_executor/layers/sampler.py
+++ b/vllm/model_executor/layers/sampler.py
@@ -13,6 +13,9 @@
 from vllm.sequence import (Logprob, PromptLogprobs, SampleLogprobs,
                            SamplerOutput, SequenceGroupOutput, SequenceOutput)
 
+# (num_token_ids, num_parent_ids) per sequence group.
+SampleResultType = List[Tuple[List[int], List[int]]]
+
 
 class Sampler(nn.Module):
     """Samples the next tokens from the model's outputs.
@@ -155,7 +158,7 @@ def _apply_min_tokens_penalty(
         have not been generated yet
     """
     # list of indices in logits that will be set to -inf
-    logits_to_penalize = []
+    logits_to_penalize: List[Tuple[int, int]] = []
     logits_applied = 0
     for seq_group in sampling_metadata.seq_groups:
         seq_ids = seq_group.seq_ids
@@ -269,7 +272,7 @@ def _apply_min_p(
 def _greedy_sample(
     selected_seq_groups: List[SequenceGroupToSample],
     samples: torch.Tensor,
-) -> List[Tuple[List[int], List[int]]]:
+) -> SampleResultType:
     """Run greedy sampling on a given samples.
 
     Args:
@@ -284,7 +287,7 @@ def _greedy_sample(
     """
     samples = samples.tolist()
     sample_idx = 0
-    results = []
+    results: SampleResultType = []
     for seq_group in selected_seq_groups:
         if not seq_group.do_sample:
             results.append(([], []))
@@ -304,7 +307,7 @@ def _greedy_sample(
 def _random_sample(
     selected_seq_groups: List[SequenceGroupToSample],
     random_samples: torch.Tensor,
-) -> List[Tuple[List[int], List[int]]]:
+) -> SampleResultType:
     """Run random sampling on a given samples.
 
     Args:
@@ -320,7 +323,7 @@ def _random_sample(
     # Find the maximum best_of value of the prompt phase requests.
     random_samples = random_samples.cpu()
     sample_idx = 0
-    results = []
+    results: SampleResultType = []
     for seq_group in selected_seq_groups:
         if not seq_group.do_sample:
             results.append(([], []))
@@ -348,7 +351,7 @@ def _random_sample(
 def _beam_search_sample(
     selected_seq_groups: List[SequenceGroupToSample],
     logprobs: torch.Tensor,
-) -> List[Tuple[List[int], List[int]]]:
+) -> SampleResultType:
     """Run beam sampling on a given samples.
 
     Args:
@@ -370,7 +373,7 @@ def _beam_search_sample(
     # NOTE: Beam search is not vectorized, so its speed can be slower than
     # other sampling methods.
     sample_idx = 0
-    results = []
+    results: SampleResultType = []
     for seq_group in selected_seq_groups:
         if not seq_group.do_sample:
             results.append(([], []))
@@ -391,16 +394,16 @@ def _beam_search_sample(
             next_token_ids = next_token_ids.tolist()
         else:
             # Generation phase.
-            cumulative_logprobs = [
+            cumulative_logprobs: List[int] = [
                 seq_group.seq_data[seq_id].cumulative_logprob
                 for seq_id in seq_ids
             ]
-            cumulative_logprobs = torch.tensor(
+            cumulative_logprobs_tensor = torch.tensor(
                 cumulative_logprobs,
                 dtype=torch.float,
                 device=seq_group_logprobs.device)
             seq_group_logprobs = (seq_group_logprobs +
-                                  cumulative_logprobs.unsqueeze(dim=1))
+                                  cumulative_logprobs_tensor.unsqueeze(dim=1))
             _, topk_ids = torch.topk(seq_group_logprobs.flatten(),
                                      2 * beam_width)
             topk_ids = topk_ids.tolist()
@@ -452,8 +455,10 @@ def _sample_with_torch(
     sampling_metadata: SamplingMetadata,
     include_gpu_probs_tensor: bool,
     modify_greedy_probs: bool,
-) -> Tuple[List[Tuple[List[int], List[int]]], Optional[torch.Tensor]]:
-    categorized_seq_group_ids = {t: [] for t in SamplingType}
+) -> Tuple[SampleResultType, Optional[torch.Tensor]]:
+    categorized_seq_group_ids: Dict[SamplingType,
+                                    List[int]] = {t: []
+                                                  for t in SamplingType}
     categorized_sample_indices = sampling_metadata.categorized_sample_indices
     for i, seq_group in enumerate(sampling_metadata.seq_groups):
         sampling_params = seq_group.sampling_params
@@ -555,8 +560,10 @@ def _sample_with_triton_kernel(
     logprobs: torch.Tensor,
     sampling_metadata: SamplingMetadata,
     sampling_tensors: SamplingTensors,
-) -> List[Tuple[List[int], List[int]]]:
-    categorized_seq_group_ids = {t: [] for t in SamplingType}
+) -> SampleResultType:
+    categorized_seq_group_ids: Dict[SamplingType,
+                                    List[int]] = {t: []
+                                                  for t in SamplingType}
     categorized_sample_indices = sampling_metadata.categorized_sample_indices
     for i, seq_group in enumerate(sampling_metadata.seq_groups):
         sampling_params = seq_group.sampling_params
@@ -632,7 +639,7 @@ def _sample(
     probs: torch.Tensor, logprobs: torch.Tensor,
     sampling_metadata: SamplingMetadata, sampling_tensors: SamplingTensors,
     include_gpu_probs_tensor: bool, modify_greedy_probs: bool
-) -> Tuple[List[Tuple[List[int], List[int]]], Optional[torch.Tensor]]:
+) -> Tuple[SampleResultType, Optional[torch.Tensor]]:
     """
     Args:
         probs: (num_query_tokens_in_batch, num_vocab)
@@ -680,7 +687,7 @@ def _get_ranks(x: torch.Tensor, indices: torch.Tensor) -> torch.Tensor:
 def _get_logprobs(
     logprobs: torch.Tensor,
     sampling_metadata: SamplingMetadata,
-    sample_results: List[Tuple[List[int], List[int]]],
+    sample_results: SampleResultType,
 ) -> Tuple[List[Optional[PromptLogprobs]], List[SampleLogprobs]]:
     """Return sample lobprobs and prompt logprobs.
 
@@ -751,8 +758,8 @@ def _get_logprobs(
         assert len(next_token_ids) == len(query_indices)
 
     if len(query_indices) == 0:
-        empty_sampled_logprob = []
-        empty_prompt_logprob = None
+        empty_sampled_logprob: SampleLogprobs = []
+        empty_prompt_logprob: Optional[PromptLogprobs] = None
         return [empty_prompt_logprob], [empty_sampled_logprob]
 
     query_indices_gpu = torch.tensor(query_indices, device=logprobs.device)
@@ -965,7 +972,7 @@ def _modify_greedy_probs_inplace(logprobs: torch.Tensor, probs: torch.Tensor,
 
 
 def _build_sampler_output(
-    sample_results: List[Tuple[List[int], List[int]]],
+    sample_results: SampleResultType,
     sampling_metadata: SamplingMetadata,
     prompt_logprobs: List[Optional[PromptLogprobs]],
     sample_logprobs: List[SampleLogprobs],
@@ -1009,7 +1016,7 @@ def _build_sampler_output(
     )
 
 
-def _get_next_prompt_tokens(seq_group: SequenceGroupToSample) -> List[str]:
+def _get_next_prompt_tokens(seq_group: SequenceGroupToSample) -> List[int]:
     """Get a list of next prompt tokens to compute logprob from a
         given sequence group.
 
diff --git a/vllm/model_executor/model_loader/tensorizer.py b/vllm/model_executor/model_loader/tensorizer.py
index 8fc6d16672117..2d654b2fefb8d 100644
--- a/vllm/model_executor/model_loader/tensorizer.py
+++ b/vllm/model_executor/model_loader/tensorizer.py
@@ -64,7 +64,7 @@ def _construct_tensorizer_args(self) -> "TensorizerArgs":
             "s3_secret_access_key": self.s3_secret_access_key,
             "s3_endpoint": self.s3_endpoint,
         }
-        return TensorizerArgs(**tensorizer_args)
+        return TensorizerArgs(**tensorizer_args)  # type: ignore
 
     def verify_with_parallel_config(
         self,
@@ -270,8 +270,10 @@ def __init__(self, tensorizer_config: TensorizerConfig,
         self.model = self._init_model()
 
     def _init_model(self):
+        assert self.tensorizer_config.hf_config is not None
         model_args = self.tensorizer_config.hf_config
         model_args.torch_dtype = self.tensorizer_config.dtype
+        assert self.tensorizer_config.model_class is not None
         with no_init_or_tensor():
             return self.tensorizer_config.model_class(
                 config=model_args,