diff --git a/docs/config/setup/interfaces/mermaid.MermaidConfig.md b/docs/config/setup/interfaces/mermaid.MermaidConfig.md
index 7cd0e7e78e..e13e4fbbf2 100644
--- a/docs/config/setup/interfaces/mermaid.MermaidConfig.md
+++ b/docs/config/setup/interfaces/mermaid.MermaidConfig.md
@@ -460,7 +460,7 @@ This is useful when you want to control how to handle syntax errors in your appl
 
 ### theme
 
-• `Optional` **theme**: `"default"` | `"forest"` | `"dark"` | `"neutral"` | `"null"`
+• `Optional` **theme**: `"default"` | `"base"` | `"dark"` | `"forest"` | `"neutral"` | `"null"`
 
 Theme, the CSS style sheet.
 You may also use `themeCSS` to override this value.
diff --git a/packages/mermaid/src/config.type.ts b/packages/mermaid/src/config.type.ts
index 2d25282f38..7bd3051836 100644
--- a/packages/mermaid/src/config.type.ts
+++ b/packages/mermaid/src/config.type.ts
@@ -61,7 +61,7 @@ export interface MermaidConfig {
    * You may also use `themeCSS` to override this value.
    *
    */
-  theme?: 'default' | 'forest' | 'dark' | 'neutral' | 'null';
+  theme?: 'default' | 'base' | 'dark' | 'forest' | 'neutral' | 'null';
   themeVariables?: any;
   themeCSS?: string;
   /**