Abstract: A cleaning device was designed for sunlight greenhouse plastic greenhouse，which was to solve problems of cleaning，low transmittance and affecting growth of crops.3D modeling was carried out based on computer aided design software Solidworks.Overall structure and key components were designed and simulated，and then experimental prototype model was built.Experimental results showed that film transmittance of greenhouse was greatly improved under condition of pure tap water and cleaning agent，highest from 51.6% to 78.3% by 26.7％，and from 51.6% to 80.6% by 29.0％.Cleaning device has a reasonable structure and obvious cleaning effect.It could meet purpose and requirements of users.