The invention discloses a torque measuring device zero value dynamic calibration method and device. The method includes the following steps that: a torque measuring device zero value dynamic calibration test device is arranged, and an engine, adopted as a power source, is used to directly drive a torque measuring device; the arranged dynamic calibration test device is adopted to perform zero valuedynamic calibration on the torque measuring device, the first actual phase of the torque measuring device at a corresponding rotation speed under a condition that a torque measured value is zero is obtained during ground slow rotation state operation, and the second actual phase of the torque measuring device at a corresponding rotation speed under a condition that a torque measured value is zerois obtained during space slow rotation state operation; and data processing is performed on the obtained first actual phase and second actual phase, and the initializations of the first actual phaseand the second actual phase are respectively set to be under the corresponding speeds of a torque measuring device control box. According to the torque measuring device zero value dynamic calibrationmethod and device provided by the invention, on-site dynamic calibration can be performed on the zero value of the torque measuring device in advance, and therefore, the accuracy and reliability of the power measurement data of a test bed can be greatly improved.