Abstract: Swing check valve is opened when the flow direction is forward, when the flow is reversed, the valve is automatically closed by back pressure. In this study, the internal flow field analysis of the valve was conducted by Fluent. The working fluid used in the study, using liquefied methane -165 ℃ (CH4) and velocity field, pressure field, pressure drop coefficient were simulated by varying separately the opening divergence into four intervals from 0 to 100%. The approximate research result are as follow : When the opening divergence is smaller, it appears high pressure on the upstream side, this value is relaxed when the opening divergence is large. Flow rate coefficient of the valve shows a larger value as the degree of opening becomes larger, confirming that the check valve used in the study is in the effective flow rate counting range. Key Words :Cryogenic, LNG, Swing Check Valve, Flow Analysis, Flow Coefficient, Pressure Drop Coefficient *†문정현(교신저자) : 선박해양플랜트연구소 해수플랜트연구센터E-mail : moonjh@kriso.re.kr, Tel : 033-630-5028 *†Jung-Hyun Moon(corresponding author) : Korea Research Institute of Ships & Ocean Engineering, Seawater Utilization Plant Research CenterE-mail : moonjh@kriso.re.kr, Tel : 033-630-5028