In this paper, density peak clustering is introduced into radar signal sorting, which can quickly find the cluster center without determining the number of clusters.The concept of density entropy is proposed by referring to potential entropy, and the cutoff distance selection algorithm of kernel function in clustering is optimized.The problem of how to automatically judge the cluster number and cluster center point is studied, the threshold function and judgment rules are designed.The allocation-merging criterion of the original algorithm is also optimized.The simulation results show the effectiveness of the algorithm.