Objective To investigate the residual stress of silicon-alloyed pyrocarbon for mechanical heart valves. Methods The silicon-alloyed pyrocarbon coating was prepared by the chemical vapor deposition method, and the composition and structure of the coating were investigated. The residual stress on the surface of the coating was studied by X-Ray diffraction and FEM. Results The results showed that the coating consisted of two phases, pyrolytic carbon and SiC, the SiC particle size was about 10 μm and uniformly dispersed in the pyrolytic carbon. The results of X-ray diffraction experiment for two samples were - 7 MPa and - 9 MPa, and the FEM result was about -6 MPa. Conclusion The residual stress of SiC was compressive stress,and the FEM result was in accordance with the experiment result. The influence of particle size on the material residual stress was not obvious.