Easy-to-overhaul drainage device for building roof

The utility model discloses an easy-to-overhaul drainage device for a building roof. The utility model relates to the technical field of roof drainage. Roof, an audible and visual alarm and an intelligent display screen are arranged on the upper surface of the roof, a gutter is arranged on one side of the roof, a liquid level sensor, a filter screen and a siphon drainage port are arranged in the gutter, a drainage pipe is arranged at the lower end of the siphon drainage port, a pressure sensor is arranged on the inner wall of the straight water falling pipe, and a connecting base is arranged at one end of the pressure sensor. According to the utility model, the pipeline made of HDPE high-density polyethylene is arranged; the large impact force can be borne; the pipeline is light in weightand convenient to construct, the position of the faulted pipeline can be known in time by arranging the liquid level sensor and the multiple pressure sensors, the situation that the pipeline is manually opened one by one for