This paper presents the design, fabrication and test of a high-efficient residential air-conditioner which won first place in the Max Tech andBeyond competition sponsored by Lawrence Berkeley National Laboratory and U.S. Department of Energy. Over 20 students and facultymembers of University Maryland participated in the one-year competition that created an air-conditioner that achieved at least 30% better COPcompared to the state-of-the-art products. The design utilizes the technologies of separate sensible and latent cooling (SSLC), low temperaturedrivendesiccant wheel (DW) and radiative heat exchangers (RHX). The SSLC technology increases the vapor compression cycle COP byelevating the evaporating temperature while the latent cooling demand is fulfilled by utilizing waste heat from the condenser to regenerate the DW.The RHX is designed to provide better thermal comfort for occupants. The preliminary test results show that the design achieves the goal byimproving the system COP by 31%. The second round of study on the SSLC system will be focused on reducing the manufacturing cost of the firstgeneration prototype and preparing for mass production.