Three-dimensional building wall external facade flatness detection device

The invention discloses a three-dimensional building wall external facade flatness detection device, which comprises a detection device body, a sealing plate, a handle, a pressing knob, a connecting hole, a mounting frame, a supporting spring and a sliding groove, and the mounting frame is arranged on the detection device body, and the front side of the mounting frame is fixedly connected with thesealing plate through the connecting hole and screws; a handle is welded to one side of the mounting frame, a rectangular protective cover is welded to the inner side of the sealing plate, a storagebin is arranged in the protective cover, a pressing rotary knob is connected to the middle of the outer side of the sealing plate through a bearing, a threaded rod is integrally formed at the inner end of the pressing rotary knob, and a jacking head is arranged on the side, away from the handle, of the mounting frame. Compared with a traditional wooden stick or a vertical long-strip-shaped rectangular stick-shaped structur