The multi span film greenhouse is a type of greenhouse that has emerged and been developed rapidly in recent years. Compared with glass greenhouse, it has the advantages of light weight, less amount of skeleton material, small shading rate of structural parts, low cost and long service life, etc. Its environmental control ability can basically reach the same level of glass greenhouse, and the acceptance ability of users of continuous greenhouse is much higher than that of glass greenhouse all over the world, so it has become the mainstream of modern greenhouse development. The multi span film greenhouse is simple and practical equipment for cultivation or breeding, it is easy to construct, convenient to use. Plastic Film Greenhouse can be used for seedling breeding, flower and fruit planting, poultry breeding, etc. In addition, it is also suitable for vegetables such as, potatoes, tomatoes, cucumbers, onions, carrots, zucchini, eggplant, okra, lettuce, etc. The greenhouse can provide the conditions of suitable illumination, moisture and temperature, raising the output and resisting the natural disasters.The multi span film greenhouse generally takes the main hot-dip galvanized steel frame as the load-bearing structure, film as the covering heat preservation material, internal and external shading, cooling fan and water curtain as the auxiliary system, because of its relatively low cost, but beautiful shape, large space and suitable for mechanization, it has been used in a large area in recent years.