AbstractA series of cellulose/soy protein membranes (CSM) was coated with chitosan to improve the mechanical properties, cytocompatibility, and hemocompatibility. The original CSM and chitosan-coated CSM (CH/CSM) were characterized by Fourier transform infrared spectroscopy, X-ray diffraction analysis, scanning electron microscopy, water contact angle testing, and tensile testing. CH/CSM had a smoother surface microstructure and enhanced mechanical properties as compared to the corresponding CSM. The cytocompatibility and hemocompatibility of CSM and CH/CSM were evaluated by cell culture, MTT assay, in vitro platelet adhesion testing, plasma recalcification time (PRT) measurement, and hemolysis assay. The higher cell adherence and improved cytocompatibility of CH/CSM were mainly ascribed to the coated composition and the altered surface microstructure of CSM. CH/CSM also showed lower platelet adhesion, longer PRT, and a lower hemolysis rate, all resulting from the good hemocompatibility of chitosan and the smoother membrane surface after chitosan coating. Undoubtedly, surface coating with chitosan improved the microstructure, mechanical properties, cytocompatibility, and hemocompatibility, thus widening the possible range of applications for cellulose/soy protein-based biomaterials.