This paper establishes the optimal thickness of TiN ceramic coating on the surface of Mg-Ca-Zn alloy using optical and scanning microscopy methods. X-ray diffraction analysis and tests on its mechanical properties showed that deposition of coating with a thickness of not less than 1 μm on the alloy causes a uniform distribution of the TiN phase over the magnesium alloy surface. The TiN coating also contributes to simultaneous increases in the yield strength, tensile strength, ductility and microhardness of the Mg-Ca-Zn alloy.