When the outline injury measurement of revolving object surface is carried out utilizing laser Doppler effect, intensity and quality of Doppler signals of the diffused light are essential parameters affecting measurement and its accuracy. In this paper, the laser Doppler reference optical system, average effect of diffused light phase random change of revolving object surface and least square fit method are studied, and a reference optical system with high signal noise ratio is designed, besides the loss signals arising from subtle structure of object surface are restructured, outline injury measurement of revolving object surface is attained with the relative error of 0.3%.