Engine unit capable of preventing infrared detection

The invention discloses an engine unit capable of preventing infrared detection. The engine unit comprises a main frame and an upper cover, wherein the main frame is connected with an air outlet of anengine assembly, the main frame is provided with an upper cover capable of being turned over, a gear is arranged on the upper cover and located at a side end of the upper cover, a rack meshed with the gear is arranged on the main frame, an end of the rack is connected with a push rod of an electric push cylinder, and the electric push cylinder is located on a side wall of the main frame. The engine unit is advantaged in that the upper cover is arranged at the air outlet of the engine assembly, when hidden movement is needed, the upper cover is turned over upwards, the upper cover just shieldsthe upper portion of the air outlet of the engine assembly at the moment, and the risk detected by the infrared detection device can be reduced through the shielding effect of the upper cover on hotair exhausted by the engine