With the ever-growing aviation industry, energy researches on aviation have turned to renewable energy sources providing electric propulsion. Fuel cells are one of the most popular sources of power for electric vehicles terms of being greener, more reliability, and higher efficiency. Among fuel cells, the most attractive option for flight is polymer electrolyte membrane fuel cells (PEMFC). This paper aims to compose of a hybrid propulsion system to a lightweight aircraft Cri-Cri for more electric aircraft concept. For this purpose, first, conceptual a hybrid propulsion system is designed for the prototype aircraft. The fuel-cell hybrid system proposed for this paper consists of electric motor, fuel cell system, battery, DC/AC converter, and DC/DC converter. Second, some analyses are done. These analyses contain required power, hydrogen consumption, energy consumption, etc.. As a result, Cri-cri needs 26 Kw during take-off, 30 Kw during climb, 10 kW during cruise, and 7 kW during descent. It also consumed 0.75 kg of hydrogen in total, including 0.21 kg in the take-off and climb, 0.42 kg in the cruise, and 0.12 in the descent. The remaining 0.25 kg of hydrogen is reserved for use in emergencies. The total amount of energy consumed is 33 kWh.