Energy savings are a major goal in our lives because energy consumption is continuously increasing. We have studied in this paper four air conditioning systems, so that each system mainly consists of a vapor compression cycle and a rotating desiccant wheel. The thermodynamic analysis for air conditioning system, the heat exchanger, the ground heat exchanger and the evaporative water spray cooler were presented. Design and operating parameters including outlet air temperature, outlet air humidity, regeneration air temperature, and desiccant wheel speed are studied to assess its effect on the performance of the systems considered. This hybrid system significantly decreases the supplied air temperature at different four Systems. When the inlet air humidity ratio and the regeneration air temperature increase, the COPth of the air conditioning system decreases. When the desiccant wheel speed increased, the COPth of the air conditioning system decreases. COPth decreases with the increasing of the cooling load for the space and also decreases with the decreasing of the inlet air humidity ratio at process air. The results show that in these four systems, COPth is the highest at system 4 which contains desiccant wheel, heat exchanger and ground source circulation achieving an improvement of about 48 % and a consequent power consumption reduction of 20 %.