Abstract: The Ming Tombs Pumping Storage Power Station is a large scale hydropower projec t with an underground power house. Locating the power house is one of the mos t important problems for the project not only in the conditions for construction but also in economic cost. The paper analyses firstly the characteristics of f aults and fractures which control the location of the power house in the area. Secondly, the surrounding rocks of the power house is classified from some phys ical and mechanical indexes. Meanwhile, the stability of surrounding rocks of th e power house is analyzed and the different geological conditions are evaluated . Finally, the engineering geological conditions considered in three plans for locating the power house are compared. It follows that the plan Ⅲ is the best one.