This paper examines the influences of informational distortion in bilateral and multilateral international trade policy coordination, and determines the optimal strategy under incomplete information. When a country owns private information about the indirect government intervention and other technical factors of its own firm, multilateral policy coordination mode is welfare dominant to the bilateral mode for a country under informational disadvantage. The world welfare is also improved with the adoption of multilateral coordination model from the initial stage of negotiation compared to bilateral one under incomplete information.