Abstract: Two kinds of polycarbonate urethane (PCU)-liquid crystal composite membranes were prepared based on cholesteryl oleyl carbonate(COC) and propoxypropyl cellulose(PPC) liquid crystal compounds by solutioncast method. The surface morphology and liquid crystal wastage rate in PBS solution of the composite membranes, and the effects of the kind and content of liquid crystal on the hemolysis ratio, dynamic blood clotting property and surface protein adsorption of composite membranes were studied. The results showed that the hemolysis ratio of two kinds of PCU-liquid crystal composite membranes were lower than 5%, conforming to the HR value of biomaterials. The property of dynamic blood clotting of two kinds of composite membranes are better than that of pure PCU. Compared to that of PCU-PPC, the property of dynamic blood clotting of PCU-COC was better, but the COC in composite membrane was prone to flow out in PBS solution. polycarbonate urethane; liquid crystal; composite membrane; blood compatibility