The utility model relates to a protective cabin door mechanism, in particular to a protective cabin door of a camera box. The cabin comprises a cabin body, a cabin cover, a lock catch device and a slide rail device, a downwards convex mounting groove is formed in the bottom of the cabin body; a camera hole is formed in the front part of the mounting groove; the hatch cover is installed on the installation groove in a sliding mode through the sliding rail device, the hatch cover can slide front and back along the inner side face of the installation groove, a spring is connected between the hatch cover and the hatch body, a lock catch device is installed on the rear portion of the hatch cover, a lock hole is formed in the rear portion of the installation groove, and the lock catch device andthe lock hole can be locked in a matched mode. According to the utility model, the hatch cover is controlled to move through the rotation motion of the steering engine by utilizing the lock catch device and the spring to achieve the effect of quickly closing the hatch cover, thereby achieving the purpose of protecting the camera.