Green vehicles include electric vehicles, natural gas vehicles, fuel cell vehicles (FCV), and vehicles running on fuel such as a biodiesel or an ethanol blend. An FCV is equipped with a cylinder valve installed in an ultra-high pressure vessel to control the hydrogen flow. For this purpose, an optimum design of the solenoid actuator is necessary to ensure reliability when driving an FCV. In this study, an electromagnetic field analysis for ensuring reliable operation of the solenoid actuator was conducted by using Maxwell V15. The electromagnetic field analysis was performed by magneto static technique, according to the distance between magnetic poles, in order to predict the attraction force. Finally, the attraction force was validated through comparison between the Maxwell results and measurement results. From the results, the error of attraction force ranged from 2.33 to 3.85 N at testing conditions.