diff --git a/src/index.ts b/src/index.ts
index cd9f456..2aff56c 100644
--- a/src/index.ts
+++ b/src/index.ts
@@ -62,8 +62,9 @@ export class Redmine {
                 }
             };
 
-            const { apiKey, username, password } = this.options;
+            const { apiKey, username, password, impersonateUser } = this.options;
 
+            // Set authentication
             if (apiKey) {
               connConfig.headers['X-Redmine-API-Key'] = apiKey;
             }
@@ -74,6 +75,11 @@ export class Redmine {
               };
             }
 
+            // Set impersonate
+            if (impersonateUser) {
+              connConfig.headers['X-Redmine-Switch-User'] = impersonateUser;
+            }
+
             this.conn = axios.create(connConfig);
         }
 
@@ -991,6 +997,7 @@ export namespace RedmineTS {
     apiKey?: string;
     username?: string;
     password?: string;
+    impersonateUser?: string;
     maxUploadSize?: number;     // Default: 5MB
   }