A modeling method of the thermal distribution in glass greenhouse with mechanica l ventilation was proposed based on the CFD technique. The flow regime, which wa s proved to be turbulent, was modelled by using the standard turbulence model，a s well as the crop model, solar radiation and thermal radiation model．The numer ical solution was made by applying a finite volume discretization code with the SIMPLE algorithm, and then the velocities and temperatures at key points were me asured in a Venlotype greenhouse. The temperature error and the mean absolute t emperature error were controlled in 3℃ and 10% respectively except few data. The results indicate that the CFDbased model is effective. 