In this study, energy, exergy and thermoeconomic analysis of a heat pump system is carried out using alternative refrigerants for residential heating. The aim of thermoeconomic optimization process is to build a relationship between the capital and operating costs and exergy losses which minimizes the system product costs for a given system configuration. For this aim, the refrigerants are selected to be R22, R134a, R410A, R404A, R290 and R600a. Using the thermodynamic properties of these refrigerants, performance parameters of the system such as COP, exergy efficiency and irreversibility rates are calculated. Additionally, some parametric studies are carried out to determine how COP, exergy efficiency and irreversibility rate of the system vary with different condenser and evaporator temperatures. Finally, optimum evaporator and condenser temperature values which affect the system performance and optimum corresponding heat exchanger area are calculated. Optimization procedure is applied for each refrigerant to present a new approach to the refrigerant selection. As a result, optimum conditions for the optimum heat exchanger area and optimum system efficiency for given conditions are determined. From the results the best refrigerant is found to be R600a, followed by R22, R134a, R290, R410A and R404A.