The invention provides an integrated motor rotating speed measuring mechanism of a sensor arranged in a motor end cover. A bearing is embedded into the center of the end cover and plays a role in supporting the rotation of a motor rotating shaft, and the end of the motor rotating shaft is embedded into a bearing inner hole; a radical magnetized permanent magnet steel is arranged in the center of the end face of the rotating shaft and rotates together with the motor rotating shaft, and senses signals in a Hall sensor chip; a circular circuit board is fixed in a circular sunken table in the center of the end cover by using screws; the Hall sensor chip is positioned in the center of the surface of the circular circuit board and used for sensing the rotation of the motor rotating shaft; and one end of a cable is directly welded on the circular circuit board, and the other end of the cable is led out of the end cover through a cable processing hole of the end cover so as to output the signals. By adopting an integrated structure, the rotating speed of a motor rotor is measured more compactly and reliably, and installation and debugging of external devices are avoided. The orthogonal pulse signals can be measured by adopting a counter, so the method is simple and reliable. Because the Hall sensor chip and the motor rotating shaft are arranged in non contact, the reliability is greatly improved.