diff --git a/src/controller/python/chip/ChipDeviceCtrl.py b/src/controller/python/chip/ChipDeviceCtrl.py
index ec53d017787927..00645dd03ef8ad 100644
--- a/src/controller/python/chip/ChipDeviceCtrl.py
+++ b/src/controller/python/chip/ChipDeviceCtrl.py
@@ -305,7 +305,7 @@ def SetWiFiCredentials(self, ssid, credentials):
 
         return self._ChipStack.Call(
             lambda: self._dmLib.pychip_DeviceController_SetWiFiCredentials(
-                ssid, credentials)
+                ssid.encode("utf-8"), credentials.encode("utf-8"))
         )
 
     def SetThreadOperationalDataset(self, threadOperationalDataset):