The utility model discloses a maintenance protective shed device of a precast concrete beam. The maintenance protective shed device comprises a truss ceiling, truss side vertical frames and truss endvertical frames. The truss ceiling forms a shed body through truss side vertical frames arranged on the two sides and truss end vertical frames arranged front and back. Fireproof heat preservation rock wool laminboards are arranged on the upper surface, the two side faces, the front face and the rear face of the shed body to form a sealed space. A lifting ring is fixed on the truss ceiling and upwards penetrates through the truss ceiling and the fireproof heat preservation rock wool sandwich plate; a maintenance water pipeline and an illumination pipeline are arranged on the truss ceiling; anatomizing spray head with a downward spray head is arranged on the maintenance water pipeline; an LED waterproof lamp is connected to the lighting pipeline. The greenhouse body is stable in structure,can be conveniently and rapidly moved to different construction areas, has multiple purposes, and has the functions of heat preservation and moisture preservation; a good environment is created for installation and processing of building construction, green construction is achieved, and safe power utilization of construction in an outdoor humid environment is guaranteed.