This paper investigates the integration of a hybrid power system for a small unmanned aerial vehicle (UAV). The proposed hybrid power system consists of hydrogen fuel cell, photovoltaic panels and battery. The UAV is modeled to have photovoltaic panels covering the wing area, proton exchange membrane fuel cell and a lithium-polymer battery. A small UAV is used for the study that has low takeoff weight and small dimensions to make the UAV man-portable. Analyses are conducted using data acquired through bench tests of the power systems and simulations. Using drag, lift and weight values, the power required by the UAV is determined. Best test measurements and simulations are conducted for the maximum required power. The flight performance of the UAV improved with the hybrid power system. The UAV endurance increased from 470 min to 970 min. The research study shows the usefulness of hybrid power system for a small UAV. Finally, the paper also establishes the effectiveness of using renewable energy sources for mobile applications.