The main structure of plastic greenhouses is generally made of hot-dip galvanized steel pipes as the main load-bearing structure, produced in factories and installed on site. Due to the light weight of the plastic greenhouse itself and its weak resistance to wind and snow loads, full consideration should be given to the overall stability of the structure. Generally, vertical slant support should be set in the second span or the second bay indoors, and necessary spatial support should also be considered in the greenhouse's outer protective structure and roof. It is best to have diagonal braces (diagonal braces) anchored to the foundation to form a spatial force system. The main structure of a plastic greenhouse should have a wind resistance of at least level 8, and generally requires a wind resistance of level 10. The snow load bearing capacity of the main structure should be determined based on the actual snowfall conditions in the construction area and the winter usage of the greenhouse. For use in the north, the designed snow load should not be less than 0.35kN/m2. For plastic greenhouses that operate on an annual basis, multiple load factors such as equipment weight, plant lifting weight, and maintenance should also be considered.