A mathematical model for predicting the performance of solar energy assisted hybrid air conditioning system (SEAHACS) is presented. The honeycombed silica gel desiccant wheel is used in this study. One-rotor six-stage rotary desiccant cooling system, (two-stage dehumidification process, two-stage pre-cooling process and two-stage regeneration process) are realized by only one wheel. Three air streams are involved in the present system. The mathematical model has been validated with the experimental data. The range of regeneration air inlet temperature changed from 65 to 140 degrees C, area ratio of process air to regeneration air change from 1 to 3.57, regeneration air inlet velocity from 1.5 to 5.5 m/s have been examined for a range of rotation speed from 6 to 20 rev/h. The optimization of these parameters is conducted based on the moisture removal capacity D, relative moisture removal capacity, dehumidification coefficient of performance and thermal coefficient of performance. At last, the influences of these main parameters on optimal rotation speed are discussed. (C) 2013 Elsevier Ltd. All rights reserved.