In this study, thermoeconomic analysis of a combined cycle power plant (CCPP) is investigated. The aim of this study is to find the minimum electricity production cost (EPC). The variable parameters selected for the optimization are the compressor pressure ratio, turbine inlet temperature, isentropic efficiencies, discount rate, etc. In the analysis, all thermodynamic and thermoeconomic expressions are formulated as a function of these decision variables. Consequently, the developed model is solved and the conditions giving minimum unit EPC for each value of variable parameters are determined.