Abstract: In order to study the opening and closing time of the vent in the tomato greenhouse, and to further realize the intelligent control of the greenhouse, this experiment combined the different growth periods of tomato, used the method of multiple regression to analyze the greenhouse temperature, and finally obtained the regression model of the opening or closing of the vent in the greenhouse at the different growth periods of tomato. At the same time, this experiment was compared with manual control, and the experimental data of this experiment included the basic temperature when the greenhouse vent was opened or closed, the temperature inside and outside the greenhouse, and the temperature difference between day and night. Through the research and analysis, we obtained three results as follows. The first result was that the prediction effect of the multiple regression model was effective. The R~2 of the prediction model of the opening or closing time of the greenhouse vent during the flowering and fruit setting period of tomatoes was 0.836 6 and 0.981 4 respectively, and the R~2 of the prediction model of the opening or closing time of the greenhouse vent during the fruiting period of tomatoes was 0.911 3 and 0.951 3 respectively, and the RMSE value of each period was less than 0.95. The second result was that the indoor temperature under the model control was optimized by 42.86% during the flowering and fruit setting period of tomatoes, compared with the manual control. The diurnal temperature difference under the control of the model was more in line with the accumulation requirements of related substances in tomato roots, stems and leaves. The last conclusion was that the model control effectively adjusted the indoor temperature variation range, improved the rationality of the temperature difference between day and night, and provided conditions for the accumulation of nutrients in tomato fruits in the fruit bearing period of tomato. In conclusion, the regression model under different growth periods of tomato can better control the opening or closing time of greenhouse vents, and also well liberate labor productivity, improve the economic benefits of tomatoes, also provide research ideas for the comprehensive regulation of tomato greenhouse.