In differential power analysis attacks (DPA), the distinguisher directly influences the effects Previous research has mainly focused on analyzing how one or more bits of the intermediate value influence the actual power consumption. However, limited study has been conducted on constructing a more effective distinguisher. In this paper, by comparing the effects of several selected distinguishers we have analyzed the structure of the distinguisher with correlation analysis. Then, we have proposed a high efficient distinguisher, named HDF and cond...