||The purpose of this paper is to suggest the calculate method of photovoltaic system government subsidies using the benefit-cost analysis. Perspectives of benefit-cost analysis for photovoltaic system government subsidies is participant, non-participant, administrator and nation. This study identifies the benefit and cost components and benefit-cost calculation procedures of photovoltaic system from four major perspectives : participant, non-participant, administrator and nation. The results of each perspective is expressed in the net present value. The results of case study of the photovoltaic system government subsidies was calculated to be 3,974,000won. Case studies following results were obtained: participant(net present value of 8,024,000won, benefit-cost ratio of 1.5, simple payback period of 5.75years), non-participant(net present value of 0won, benefit-cost ratio of 1.0), administrator(net present value of ? 14,290,000won, benefit-cost ratio of 0.22)and nation(net present value of 1,791,000won, benefit-cost ratio of 1.08).