Greenhouses provide a facility which maintains a suitable temperature for vegetable growth during the cold season in northern China by using solar radation only. However, additional resources and energy consumption, and the special climate formed in greenhouses may result in various kinds of environmental problems. Most of previous studies had been focused on a specific environmental problem,and few assessed the integrated environmental impact of a solar greenhouse planting system. The integrated environmental impact of tomato production in greenhouses was assessed by using life cycle assessment ( LCA) methodology in this study. Primary data were collected from 10 solar greenhouses and 5 plastic greenhouses at suburban Xi'an, China. Tomatoes were planted twice a year at all 10 solar greenhouses, while watermelons were planted in spring and tomatoes were planted in autumn at 5 plastic greenhouses. The environmental impacts of greenhouses construction and maintenance, agricultural materials production, planting period, and the whole greenhouses planting system were analyzed. The results showed that the environmental impact potential of producing 1000 kg tomatoes in solar greenhouses were 1740.58 MJ for energy depletion, 50.767 m3 for water depletion, 271.943 kg for global warming, 2.151 kg for acidification, 0.247 kg for eutrophication, 0.157 kg for photochemical oxidation formation, 24.217 kg for terrestrial ecotoxicity, 19.545 kg for Fresh water aquatic ecotoxicity, and 0. 124 kg for Human toxicity, respectively. For plastic greenhouses, these corresponding environmental impact potentials were 1502.346 MJ, 53.734 m3, 239.163 kg, 1.88 kg, 0.305 kg, 0.109 kg, 31.686 kg, 19.7 kg and 0.304 kg, respectively. Although the use of greenhouses made the tomato planting possible during the whole year,its construction and maintenance caused some major environmental problem,such as energy depletion,global warming, acidification and photochemical oxidation formation. Greenhouses also resulted in high temperature, high humidity and a poorly ventilated environment, which was a main cause of serious plant diseases and insect pests in greenhouses. Thus, a large amount of pesticides were used frequently in solar greenhouses. The main environmental problems during the planting period were water depletion,eutrophication,global warming,terrestrial ecotoxicity and fresh water aquatic ecotoxicity. The main environmental problems from the fertilizer and pesticides production were energy depletion. The main materials resulting in environmental problems were steel, polyethylene, nitrogen fertilizer, pesticides and organic manure with excess heavy metal. The environmental impact which was caused by a greenhouse planting system could not be ignored. For a sustainable development of greenhouse planting systems, more studies should be targeted on creating green construction materials and new structure, improving greenhouse climate, regulating fertilizers and water, as well as using green pesticides in order to diminish the environmental impact of the whole system.