The aluminum micro-channel heat exchanger consists of flat tubes, headers and louver fins, with a hydraulic diameter of Dh<1.5mm. It has the advantages of small thermal resistance, large heat transfer area, small size and light weight. Key technologies include (1) development of performance calculation software for aluminum heat exchangers, design of geometry, refrigerant flow distribution, circuits, etc. (2) mold development (3) performance test comparison, the error between the design value and the measured capacity value is ± within 5％.