Abstract: In this paper, a new type gas compressor is advaced. Because of changing the sliding friction of vane into the rolling friction and making use of the vapor-latent heat of water, the compress power and the exhaust temperature of this machine are redued obviously. The principle construction and composition program of this type compressor, computing method of thermal and geomtrical parameters, the design of the compressor are described. The computation has done to compare this type compressor with reciprocating air compressor.