The utility model discloses a top beam device of a mining excavator shed, relates to a mining face shovel type excavator, and solves the technical problem that parts are difficult to dismount during maintenance of the excavator and the technical problem of potential hazard of rain leakage from electrical clearance. According to the top beam device, a top beam arrangement mode is adjusted; a C-shaped steel structure is arranged at a steel wire rope outlet; and a middle beam is segmented in the transverse direction to respectively form a lifting mechanism region, a back rotation mechanism region, an electrical clearance region and a front rotation mechanism region. The top beam device is used in a large-size mining face shovel type excavator shed and has the advantages of simplicity in mounting and dismounting of a top beam and low maintenance cost; and the potential hazard of rain leakage from electrical clearances is avoided.