Abstract: Based on the irregular situation of the current greenhouse span in Inner Mongolia Autonomous Region, comparative analysis of this experiment were done about light and heat characteristics, yield, production costs and investment output ratio of ChiFeng greenhouse span 8.0m,8.5m,9.0m,9.5m,10m, the results showed that： in other construction parameters unchanged, in the present experimental conditions, with greenhouse span increasing, transmittance, air temperature, air humidity, soil temperature gradually became excellent; mean yield gradually increased, lOm span greenhouse tomato year average yield 9310.4kg/667m2 was significantly higher than 8m span 8470.6kg/667m2 in winter; construction costs, acres of depreciation costs, production costs were increasing, but the input-output ratio also increased, lOm span input-output ratio of 1：3.8,8m span 1：3.6.