Abstract: In radar target recognition based on high resolution range profile, power transform is a common nonlinear preprocessing method, which can improve the recognition rate. But the performance of high resolution range profile target recognition with power transform is seriously affected by signal-to-noise ratio, and the recognition result is significantly affected by the choice of the power transform exponential, even the effect is adverse. In this paper, logarithm transform is raised for high resolution range profile preprocessing to solve the problems of power transform, and a comparative analysis of the similarities and differences between the mechanism of logarithm transform and power transform is provided, and the impact of logarithm transform on the intra-class and inter-class correlation coefficients of high resolution range profiles is analyzed. The results show that logarithm transform is more suitable for high resolution range profile preprocessing than power transform, and the experimental results based on measured data show that logarithm transform can more effectively improve the recognition rate than power transform.