Abstract: The three-dimensional surface morphology of grinding wheel is very important to ensure its grinding quality. A high precision two-dimensional displacement sensor is used to measure the surface topography of grinding wheel on-line, and then the evaluation parameters of the three-dimensional surface topography of grinding wheel are calculated by establishing the reference plane of the three-dimensional topography of grinding wheel and digital filtering method.The results show that the evaluation parameters are basically the same as those measured by Zeta automatic three-dimensional measurement system, which verifies the validity and practicability of the evaluation method, and can provide indexes for grinding wheel dressing and grinding.