Based on rotation angle measurement function by photo-electricity multiple code-tracks technology, proposed a improved method of torque measurement by photoelectric technology. With MSP430 process the signal of the encoder. The encoder output E signals with a fixed difference phase, So each count cycle were subdivided into E by the rest of the E-1 signals, have Estates. Using processing unit I/O ports read the state of these signals when interrupt of Timer, Calculate the state and the torque, which sub-division of the relative rotation angle, improved torque measurement accuracy. And the torque measurement of real-time signal was transmissed to the host computer for processing and displaying, analysis the torque signal of the vibration.