In order to research the cooling effect in nature ventilation of full open-roof glass greenhouse, the CFD model was established by the k—ε turbulence and DO radiation model with high solar radiation and weak wind weather. The simulated values of the model and measured values were contrasted, and the average relative error was 2.5%. The experiment of cooling control measurements in greenhouse was carried out by using verification model. The results of experiments showed that under current natural ventilation conditions, the greenhouse gables ventilated by fanwindow and air holes of dry wet curtain. Outdoor air entered into greenhouse in horizontal direction with no upward movement velocity components. The ventilated effect of side window combined with the skylight window was poor under this condition. There was largearea air, which flowed slowly in the greenhouse. After the modification of side window structure, the airflow direction was led to generate upward velocity components when it entered into greenhouse from south gable. The ventilated effect of side window combined with skylight window was improved. The opening angle of skylight should be matched with side window, which can enhance the ventilation cooling effect. When the angle of side window was 45°, and the skylight was adjusted to 60°, the overall cooling effect of the greenhouse was better than those under other conditions which the angle of opening skylight was 45° or 75°. The overall temperature of the greenhouse was decreased from 38.4℃ to 36.9℃ and the cooling effect was improved obviously after using side window combined with roof window, when the opening angle of skylight was reasonably coordinated with side window.