Multilayer films consisting of polyethylenimine (PEI) and heparin were successfully prepared on biomedical 316L stainless steel surface via electrostatic self-assembly (ESA) of the PEI and heparin. The process of ESA of PEI/heparin was monitored bystatic contact angle, electrochemical impedance spectroscopy (EIS), reflection adsorption spectroscopyand X-rayphotoelectron spectroscopydata. The contact angle and EIS data revealed that the multilayer coating was stable in Tris-HCl (pH7.35) buffer solution for 21 days. The static platelet adhesion and static clotting time experiments indicated that the PEI/heparin-deposited stainless steel could resist the platelet adhesion and prolong the static clotting time effectively. Such an easy processing and shapeindependent method mayhave good potential for surface modification of cardiovascular devices.