Energy and environment has been issues concerned all over the world. In China, the application of small size gas-fired air-cooled air-conditioner as an alternative for electric compression air conditioning systems has shown broad prospects due to occurrence of electricity peak demand, lack of water resources and environment-friendly working pairs. Especially, the new air-cooled air-conditioner has many advantages. In order to evaluate its cycle performance, the mathematical model of the new air-conditioner was presented. After algorithm of the model and code program were made, the amount of heat recovery from refrigerant was calculated, and influence of solution distribution ratio into high pressure generator, outdoor air temperature and inlet temperature of cooled water to the evaporator on the cycle performance was evaluated. Results indicated that heat recovery contributed to energy-conservation and COP boost. Solution distribution ratio had an obvious influence on the performance of the system.