With worldwide efforts to increase the portion of renewable energy for CO2 reductions, a lot of attention has been paid to P2G (power-to-gas) in Europe and Japan to efficiently utilize the surplus electricity. In this paper, economic feasibility analysis has been carried out for P2G using PEM water electrolysis by reflecting current economic status in Korea. In addition, efficiency and electricity price required to be competent in Korean market were provided. Based on cash flow diagrams, unit production costs for H2 and CH4 were estimated and profitability of P2G using PEM water electrolysis was analyzed.