Abstarct: In this thesis, with a comprehensive approach the energy, environmental and economic analyses of an combined cooling, heating and power (trigeneration) systems baxsed on the Stirling engine have been performed. The system consists of two parallel beta type Stirling engines as the prime mover, a heat recovery system, an absorption chiller, and a power generator. present system can use for residential application. The analysis of the Stirling engine is a non-ideal adiabatic analysis. To increase the modeling accuracy, the frictional and thermal losses of Stirling engine were considered. The non-ideal adiabatic analysis was done using a developed numerical code in MATLAB software. For model validation, the operational and geometrical parameters of a GPU-3 Stirling engine were applied and the results were compared with the experimental data and other previous models. Also two beta-type Stirling engines, were proposed as prime mover in trigeneration system. Moreover, the energy modeling of absorption chiller was performed using Stirling engine waste heat. Then, the effects of engine rotational speed, regenerator length and wall temperature of heater on efficiency, Trigeneration Primary Energy Saving (TPES), Trigeneration CO2 Emission Reduction (TCO_2 ER) and Operational Cost Reduction (CR) of trigeneration system were studied and the optimum values were presented. The results showed that the best values for electric power, thermal power and cooling power at 22.53, 21.65, and 14.43 kW, respectively and also the electrical efficiency and trigeneration efficiency were 27.78% and 72.28%, respectively. Furthermore, the fuel consumption, carbon dioxide emission and operational cost of this system encountered reduction of 31.3%, 38% and 78.8% in comparison with conventional systems to produce the same amount of energy for buildings.