Huangzhuang-Gaoliying fault is a relatively large buried active fault across Beijing urban area. It is the tectonic belt of Beijing depression and Xishan uplift. The study area is located in the Future Science and Technology City in Changping. In this paper, the authors analyzed the structure and activity of the fault with the methods of shallow seismic exploration, high density resistivity method and trench profile. The results show that Huangzhuang-Gaoliyang fault is a fault zone that consists of the major fault and secondary faults. The fault belt in bedrock is mainly manifested as step fault and extends up to Quaternary, being a "Y" fault combination. Research shows that this fault has been strongly active since Holocene. Thus, the combination of three methods of shallow seismic exploration, high-density electrical and trenches is significant for detecting the buried fault in the city and exploring its activity, and it is also very important in applying practical assessment to reducing urban seismic hazard.