Abstract: After disproposed by pre-immersed water dispersive PU membranes,PU membranes grafted with the silk fibroin (SF) protein or the silk fibroin peptide(SP) protein were successfully prepared by the technique of plasma.The surface properties of the various membranes were analyzed by SEM,ATR-FTIR spectra and X-ray energy spectra.The results showed that after grafted with SF or SP protein,the hydrophilicity of PU membrane was improved,and the mechanical properties and water vapor permeabilities of the modified membranes were basically the same as that of PU membrane.