diff --git a/docs/pages/material-ui/api/text-field.json b/docs/pages/material-ui/api/text-field.json
index 0a8c3f72ccb8ce..b66de57e7eecc0 100644
--- a/docs/pages/material-ui/api/text-field.json
+++ b/docs/pages/material-ui/api/text-field.json
@@ -66,7 +66,8 @@
       "type": {
         "name": "union",
         "description": "'medium'<br>&#124;&nbsp;'small'<br>&#124;&nbsp;string"
-      }
+      },
+      "default": "'medium'"
     },
     "slotProps": {
       "type": {
diff --git a/packages/mui-material/src/TextField/TextField.d.ts b/packages/mui-material/src/TextField/TextField.d.ts
index 8afd09bcf4b2e5..28f7c230e0c1dc 100644
--- a/packages/mui-material/src/TextField/TextField.d.ts
+++ b/packages/mui-material/src/TextField/TextField.d.ts
@@ -188,6 +188,7 @@ export interface BaseTextFieldProps
   SelectProps?: Partial<SelectProps>;
   /**
    * The size of the component.
+   * @default 'medium'
    */
   size?: OverridableStringUnion<'small' | 'medium', TextFieldPropsSizeOverrides>;
   /**
diff --git a/packages/mui-material/src/TextField/TextField.js b/packages/mui-material/src/TextField/TextField.js
index 4417ee05f0910a..74bf4578371872 100644
--- a/packages/mui-material/src/TextField/TextField.js
+++ b/packages/mui-material/src/TextField/TextField.js
@@ -431,6 +431,7 @@ TextField.propTypes /* remove-proptypes */ = {
   SelectProps: PropTypes.object,
   /**
    * The size of the component.
+   * @default 'medium'
    */
   size: PropTypes /* @typescript-to-proptypes-ignore */.oneOfType([
     PropTypes.oneOf(['medium', 'small']),