diff --git a/apps/api/src/answer-evaluation/answer-evaluation.constants.ts b/apps/api/src/answer-evaluation/answer-evaluation.constants.ts
new file mode 100644
index 0000000..c4fbb8a
--- /dev/null
+++ b/apps/api/src/answer-evaluation/answer-evaluation.constants.ts
@@ -0,0 +1,22 @@
+const AccuracyEval = {
+  PERFECT: 'PERFECT',
+  MINOR_ERROR: 'MINOR_ERROR',
+  WRONG: 'WRONG',
+} as const;
+type AccuracyEval = (typeof AccuracyEval)[keyof typeof AccuracyEval];
+
+const LogicEval = {
+  CLEAR: 'CLEAR',
+  WEAK: 'WEAK',
+  NONE: 'NONE',
+} as const;
+type LogicEval = (typeof LogicEval)[keyof typeof LogicEval];
+
+const DepthEval = {
+  DEEP: 'DEEP',
+  BASIC: 'BASIC',
+  NONE: 'NONE',
+} as const;
+type DepthEval = (typeof DepthEval)[keyof typeof DepthEval];
+
+export { AccuracyEval, LogicEval, DepthEval };
diff --git a/apps/api/src/answer-evaluation/answer-evaluation.entity.ts b/apps/api/src/answer-evaluation/answer-evaluation.entity.ts
new file mode 100644
index 0000000..2ffe4f2
--- /dev/null
+++ b/apps/api/src/answer-evaluation/answer-evaluation.entity.ts
@@ -0,0 +1,56 @@
+import {
+  Entity,
+  PrimaryGeneratedColumn,
+  Column,
+  CreateDateColumn,
+  OneToOne,
+  JoinColumn,
+} from 'typeorm';
+import {
+  AccuracyEval,
+  LogicEval,
+  DepthEval,
+} from './answer-evaluation.constants';
+import { AnswerSubmission } from 'src/answer-submission/answer-submission.entity';
+
+@Entity('answer_evaluations')
+class AnswerEvaluation {
+  @PrimaryGeneratedColumn()
+  id: number;
+
+  @Column({ name: 'submission_id', type: 'int' })
+  submissionId: number;
+
+  @Column({ name: 'feedback_message', type: 'text' })
+  feedbackMessage: string;
+
+  @Column({ name: 'detail_analysis', type: 'jsonb' })
+  detailAnalysis: any;
+
+  @Column({ name: 'score_details', type: 'jsonb' })
+  scoreDetails: any;
+
+  @Column({ name: 'accuracy_eval', type: 'enum', enum: AccuracyEval })
+  accuracyEval: AccuracyEval;
+
+  @Column({ name: 'logic_eval', type: 'enum', enum: LogicEval })
+  logicEval: LogicEval;
+
+  @Column({ name: 'depth_eval', type: 'enum', enum: DepthEval })
+  depthEval: DepthEval;
+
+  @Column({ name: 'has_application', type: 'boolean', default: false })
+  hasApplication: boolean;
+
+  @Column({ name: 'is_complete_sentence', type: 'boolean', default: false })
+  isCompleteSentence: boolean;
+
+  @CreateDateColumn({ name: 'created_at', type: 'timestamp' })
+  createdAt: Date;
+
+  @OneToOne(() => AnswerSubmission)
+  @JoinColumn({ name: 'submission_id' })
+  submission: AnswerSubmission;
+}
+
+export { AnswerEvaluation };
diff --git a/apps/api/src/answer-submission/answer-submission.constants.ts b/apps/api/src/answer-submission/answer-submission.constants.ts
new file mode 100644
index 0000000..0809530
--- /dev/null
+++ b/apps/api/src/answer-submission/answer-submission.constants.ts
@@ -0,0 +1,20 @@
+const QuizMode = {
+  DAILY: 'DAILY',
+  INTERVIEW: 'INTERVIEW',
+} as const;
+type QuizMode = (typeof QuizMode)[keyof typeof QuizMode];
+
+const InputType = {
+  VOICE: 'VOICE',
+  TEXT: 'TEXT',
+} as const;
+type InputType = (typeof InputType)[keyof typeof InputType];
+
+const ProcessStatus = {
+  PENDING: 'PENDING',
+  DONE: 'DONE',
+  FAILED: 'FAILED',
+} as const;
+type ProcessStatus = (typeof ProcessStatus)[keyof typeof ProcessStatus];
+
+export { QuizMode, InputType, ProcessStatus };
diff --git a/apps/api/src/answer-submission/answer-submission.entity.ts b/apps/api/src/answer-submission/answer-submission.entity.ts
new file mode 100644
index 0000000..2ab5576
--- /dev/null
+++ b/apps/api/src/answer-submission/answer-submission.entity.ts
@@ -0,0 +1,75 @@
+import {
+  Entity,
+  PrimaryGeneratedColumn,
+  Column,
+  CreateDateColumn,
+  ManyToOne,
+  JoinColumn,
+  OneToOne,
+} from 'typeorm';
+import {
+  QuizMode,
+  InputType,
+  ProcessStatus,
+} from './answer-submission.constants';
+import { Question } from 'src/question/question.entity';
+import { AudioAsset } from 'src/audio-asset/audio-asset.entity';
+
+@Entity('answer_submissions')
+class AnswerSubmission {
+  @PrimaryGeneratedColumn()
+  id: number;
+
+  @Column({ name: 'quiz_mode', type: 'enum', enum: QuizMode })
+  quizMode: QuizMode;
+
+  @Column({ name: 'input_type', type: 'enum', enum: InputType })
+  inputType: InputType;
+
+  @Column({ name: 'raw_answer', type: 'text' })
+  rawAnswer: string;
+
+  @Column({ name: 'taken_time', type: 'int' })
+  takenTime: number;
+
+  @Column({ type: 'int', default: 0 })
+  score: number;
+
+  @CreateDateColumn({ name: 'submitted_at', type: 'timestamp' })
+  submittedAt: Date;
+
+  @Column({
+    name: 'stt_status',
+    type: 'enum',
+    enum: ProcessStatus,
+    default: ProcessStatus.PENDING,
+  })
+  sttStatus: ProcessStatus;
+
+  @Column({
+    name: 'evaluation_status',
+    type: 'enum',
+    enum: ProcessStatus,
+    default: ProcessStatus.PENDING,
+  })
+  evaluationStatus: ProcessStatus;
+
+  @Column({ name: 'user_id', type: 'int' })
+  userId: number;
+
+  @Column({ name: 'question_id', type: 'int' })
+  questionId: number;
+
+  @Column({ name: 'audio_asset_id', type: 'int' })
+  audioAssetId: number;
+
+  @ManyToOne(() => Question)
+  @JoinColumn({ name: 'question_id' })
+  question: Question;
+
+  @OneToOne(() => AudioAsset)
+  @JoinColumn({ name: 'audio_asset_id' })
+  audioAsset: AudioAsset;
+}
+
+export { AnswerSubmission };
diff --git a/apps/api/src/audio-asset/audio-asset.entity.ts b/apps/api/src/audio-asset/audio-asset.entity.ts
new file mode 100644
index 0000000..45e27dc
--- /dev/null
+++ b/apps/api/src/audio-asset/audio-asset.entity.ts
@@ -0,0 +1,27 @@
+import {
+  Entity,
+  PrimaryGeneratedColumn,
+  Column,
+  CreateDateColumn,
+} from 'typeorm';
+
+@Entity('audio_assets')
+class AudioAsset {
+  @PrimaryGeneratedColumn()
+  id: number;
+
+  @Column({ name: 'storage_url', type: 'text' })
+  storageUrl: string;
+
+  // BIGINT는 JS에서 범위 문제로 string으로 반환
+  @Column({ name: 'byte_size', type: 'bigint' })
+  byteSize: string;
+
+  @Column({ name: 'duration_ms', type: 'int' })
+  durationMs: number;
+
+  @CreateDateColumn({ name: 'created_at', type: 'timestamp' })
+  createdAt: Date;
+}
+
+export { AudioAsset };
diff --git a/apps/api/src/category/category.entity.ts b/apps/api/src/category/category.entity.ts
new file mode 100644
index 0000000..22a8815
--- /dev/null
+++ b/apps/api/src/category/category.entity.ts
@@ -0,0 +1,18 @@
+import { Entity, PrimaryGeneratedColumn, Column } from 'typeorm';
+
+@Entity('categories')
+class Category {
+  @PrimaryGeneratedColumn()
+  id: number;
+
+  @Column({ type: 'varchar', length: 255 })
+  name: string;
+
+  @Column({ name: 'parent_id', type: 'int', nullable: true })
+  parentId: number | null;
+
+  @Column({ type: 'int', default: 1 })
+  depth: number;
+}
+
+export { Category };
diff --git a/apps/api/src/question-solution/question-solution.entity.ts b/apps/api/src/question-solution/question-solution.entity.ts
new file mode 100644
index 0000000..aae8c05
--- /dev/null
+++ b/apps/api/src/question-solution/question-solution.entity.ts
@@ -0,0 +1,45 @@
+import { Question } from 'src/question/question.entity';
+import {
+  Entity,
+  PrimaryGeneratedColumn,
+  Column,
+  CreateDateColumn,
+  OneToOne,
+  JoinColumn,
+} from 'typeorm';
+
+@Entity('question_solutions')
+class QuestionSolution {
+  @PrimaryGeneratedColumn()
+  id: number;
+
+  @Column({ name: 'question_id', type: 'int' })
+  questionId: number;
+
+  @Column({ name: 'reference_source', type: 'varchar', length: 255 })
+  referenceSource: string;
+
+  @Column({ name: 'standard_definition', type: 'text' })
+  standardDefinition: string;
+
+  @Column({ name: 'technical_mechanism', type: 'jsonb' })
+  technicalMechanism: any;
+
+  @Column({ name: 'key_terminology', type: 'jsonb' })
+  keyTerminology: any;
+
+  @Column({ name: 'practical_application', type: 'text' })
+  practicalApplication: string;
+
+  @Column({ name: 'common_misconceptions', type: 'text' })
+  commonMisconceptions: string;
+
+  @CreateDateColumn({ name: 'created_at', type: 'timestamp' })
+  createdAt: Date;
+
+  @OneToOne(() => Question)
+  @JoinColumn({ name: 'question_id' })
+  question: Question;
+}
+
+export { QuestionSolution };
diff --git a/apps/api/src/question/question.entity.ts b/apps/api/src/question/question.entity.ts
new file mode 100644
index 0000000..17ab982
--- /dev/null
+++ b/apps/api/src/question/question.entity.ts
@@ -0,0 +1,38 @@
+import { Category } from 'src/category/category.entity';
+import {
+  Entity,
+  PrimaryGeneratedColumn,
+  Column,
+  JoinColumn,
+  OneToOne,
+} from 'typeorm';
+
+@Entity('questions')
+class Question {
+  @PrimaryGeneratedColumn()
+  id: number;
+
+  @Column({ type: 'varchar', length: 255 })
+  title: string;
+
+  @Column({ type: 'text' })
+  content: string;
+
+  @Column({ name: 'tts_url', type: 'varchar', length: 255, nullable: true })
+  ttsUrl: string;
+
+  @Column({ name: 'avg_score', type: 'float', default: 0 })
+  avgScore: number;
+
+  @Column({ name: 'avg_importance', type: 'float', default: 0 })
+  avgImportance: number;
+
+  @Column({ name: 'category_id', type: 'int', nullable: true })
+  categoryId: number;
+
+  @OneToOne(() => Category)
+  @JoinColumn({ name: 'category_id' })
+  category: Category;
+}
+
+export { Question };