Hemocompatibility of a biomaterial is determined by the interactions between its surface and blood. Due to the complicated action mechanism, various effective ways and the multiple affective factors of the hemocompatibility, a comprehensive evaluation needs to be built instead of single index. Therefore, the platelet consumption ratio of 10 kinds of biomaterials including Ti6Al4V-TiC-DLC gradient coat material was studied based on image analysis method. Combined with the kinetic clotting time and the hemolysis ratio, the comprehensive hemocompatibility evaluation of the material is carried out based on the improved principal component analysis. First, linear transformation of negative index is carried out. Second, index is under a dimensionless using the logarithmic treatment, then to acquire all variants’ principal component and their characteristic vectors. Finally, comprehensive evaluation index of hemocompatibility is constructed. The improved principal component analysis avoids the effect of correlativity among indexes during anaphase evaluation, and can more correctly maintain the original information of indexes. Thus, the research provides a new idea to the comprehensive evaluation of Hemocompatibility.