It relates to an energy utilization and recovery unit type all-air air conditioning system in heat ventilation and air conditioner engineering. It comprises return bellow, exhaust bellow, entry bellow and new bellow, with exhaust valves set between the return and exhaust bellows, return valve set between the return and entry bellows, new valve set between the entry and new bellows and by-pass valve between the new and exhaust bellows. The return bellow is made of air return, controller and return air filter. The exhaust bellow is made of exhaust outlet, exhaust machine and exhaust condenser. The entry bellow is composed of entry, reheated condenser, entry machine, humidifier, and evaporator. And the new bellow is composed of new wind filter, new wind inlet, and compressor. Through optimized combination of all the bellows, program self controlled running for corresponding air flow channels regulating under different running conditions, it can realize the best energy utilization and recovery. The all-air air conditioning system can be used for big space air conditioner, multi process air conditioner and those demanded whole year running.