Abstract: Insect-proof screens can distintly increase the resistance of the greenhouse ventilation systems, but now people are short of the test information. In this paper, the resistance of some different density insect-proof screens under different wind velocities were experimented and analyzed, and the resistance equations of which were regressed. In the last of the paper, the authors gave some suggestions on selecting of insect-proof screens resistance coefficient, which can provide references for the greenhouse ventilation design.