Abstract: The double-effect NH3-H2O absorption cycle is a novel efficient and compact coupled cycle that uses the absorption heat of high temperature cycle to provide the heat for the generation process of low temperature cycle. Mathematical simulation models were established to calculate and analyze refrigeration performance indices at varying temperatures of heat source，cooling water and evaporation，as well as differential concentration of solution. A comparison of coefficient of performance(COP)of the new double-effect NH3-H2O absorption cycle was made with those of for the traditional single-effect and doublestage cycles. The results showed that the double-effect NH3-H2O absorption cycle had higher COP value at cooling water temperature lower than 30℃ and evaporation temperature higher than -15℃.However，the temperature of heat source should be higher than that of the other two reference cycles.