The polycarbonate (PC) greenhouse is preferred Venlo type (also can use circular arch type), using a multi span roof, with shape of modern, stable structure, beautiful form, smooth version, remarkable thermal insulation performance, moderate light transmission rate, many rainy grooves, large span, drainage volume, strong wind resistance ability, suitable for area of big wind and rainfall. PC greenhouse has good light transmittance, low heat conduction coefficient. The polycarbonate sheet has good characteristics of good light transmittance, long service life, tensile strength, and the simple steel structure is able to meet the requirements of anti-wind and snow, and it has long service life, beautiful appearance and can reduce the repeated construction and investment, so it is first choice currently instead of the plastic film greenhouse and glass greenhouse.