Slopes near a dam body can be categorized into 4 groups, such as right and left abutment slopes, reservoir slopes, slopes along the access road and slopes along the relocated road. For each of the geological investigation, the design standards, the evaluation methods of safety and the maintenance methods, both abutment slopes in the four dams have different characteristics from the conventional cut slopes in that they can severely affect the dam safety. From this point of view this study compares and analyzes the geological investigation methods, the status of design and construction, evaluation method of safety, and monitoring & maintaining methods for four major dams in Korea, such as Soyanggang dam, 'Andong dam, Chungju dam and Boryong dam.