An optical connector defining a receiving space for receiving a corresponding plug includes an insulative housing, an optical module mounted to the insulative housing, and a protecting mechanism assembled into the receiving space. The insulative housing has a front surface at a rear side of the receiving space. The optical module has a light receiving element located behind the front surface and forwardly exposed to the receiving space. The protecting mechanism has a door lying in a vertical plane in front of the front surface to shield the light receiving element along an insertion direction when the plug is not inserted into the receiving space, and moving downwardly out of the receiving space to unveil said light receiving element in said insertion direction when the plug is inserted into the receiving space.