The invention provides a motor end cover geometric tolerance measurement device and measurement method. The motor end cover geometric tolerance measurement device comprises a correction device and a detection device, and the detection device comprises a main shaft (1), a detection unit and a datum positioning part arranged on the main shaft (1); and the main shaft (1) is rotatably arranged on thecorrection device and corrects the coaxiality through the correction device, the datum positioning part is arranged on the main shaft (1), a motor end cover (17) is arranged on the datum positioning part, and the detection unit is used for detecting the geometric tolerance of the motor end cover (17). According to the motor end cover geometric tolerance measurement device and measurement method, the geometric tolerance of the end cover can be quickly measured, and a measurement result is accurate and reliable.