In this study, a fuzzy logic controlled synchronous buck converter design has been realized to produce hydrogen with electrolysis. Electrical energy obtained from solar panels which is one of the renewable energy sources is used as energy sources. The aim of the proposed buck converter is to obtain constant output current at variable loads and variable input voltages. PWM technique is used for controlling of switches on the system. Fuzzy Logic Controller is used as control algorithm. Proposed system has been tested at variable loads and variable supply voltages using both PI controller and fuzzy logic controller to show the effectiveness of the fuzzy control algorithm. According to the experimental results, fuzzy logic controller has faster response time and has lower overshot and less steady state error than PI controller.