diff --git a/src/auth/auth-config.ts b/src/auth/auth-config.ts
index ce45713f97..a640cc3534 100644
--- a/src/auth/auth-config.ts
+++ b/src/auth/auth-config.ts
@@ -1451,3 +1451,68 @@ export class OIDCConfig implements OIDCAuthProviderConfig {
     };
   }
 }
+
+/**
+* Enforcement state of reCAPTCHA protection.
+*   - 'OFF': Unenforced.
+*   - 'AUDIT': Assessment is created but result is not used to enforce.
+*   - 'ENFORCE': Assessment is created and result is used to enforce.
+*/
+export type RecaptchaProviderEnforcementState =  'OFF' | 'AUDIT' | 'ENFORCE';
+
+/**
+* The actions for reCAPTCHA-protected requests.
+*   - 'BLOCK': The reCAPTCHA-protected request will be blocked.
+*/
+export type RecaptchaAction = 'BLOCK';
+
+/**
+* The config for a reCAPTCHA action rule.
+*/
+export interface RecaptchaManagedRule {
+ /**
+  * The action will be enforced if the reCAPTCHA score of a request is larger than endScore.
+  */
+ endScore: number;
+  /**
+  * The action for reCAPTCHA-protected requests.
+  */
+ action?: RecaptchaAction;
+}
+
+/**
+ * The key's platform type: only web supported now.
+ */
+export type RecaptchaKeyClientType = 'WEB';
+
+/**
+ * The reCAPTCHA key config.
+ */
+export interface RecaptchaKey {
+  /**
+   * The key's client platform type.
+   */
+  type?: RecaptchaKeyClientType;
+
+  /**
+   * The reCAPTCHA site key.
+   */
+   key: string;
+}
+
+export interface RecaptchaConfig {
+ /**
+  * The enforcement state of email password provider.
+  */
+ emailPasswordEnforcementState?: RecaptchaProviderEnforcementState;
+
+ /**
+  *  The reCAPTCHA managed rules.
+  */
+ managedRules: RecaptchaManagedRule[];
+
+ /**
+  * The reCAPTCHA keys.
+  */
+ recaptchaKeys?: RecaptchaKey[];
+}