Abstract: Equation between inter-yarn air permeability and parameters of fabric structure was deduced based on Hagen-Poiseuille law of hydromechanics.But the effect of fabric factors such as average float, total cover is not clear from theory, so stepwise regression analysis was used to discuss their effect on air permeability, and then regression equation between air permeability and fabric texture parameters was achieved.It can be used to predict the fabric air permeability by the test of new samples.