Abstract: In view of the problems of large number of BOP and large land area in nuclear power plants,this paper makes an in-depth study on the factors that have a great influence on the scale of land use in general layout.Studied the design optimization and layout rationality of nuclear power plant，through sorting out sub-item functions,merging and optimizing sub-items,optimizing layout of general plane functional area,optimizing transportation streamline and optimizing layout of construction facilities.The work can save land and improve economy,reserve land reasonably to ensure the sustainable development of power plant.