C-SiC coatings were prepared on stainless steel substrate by the middle frequency magnetron sputtering （MFMS） and ion beam mixing technique. After deposition, these samples were implanted by 5 keV hydrogen ion beam at a dose of 1×1018 ion/cm2. Some samples were heat treated at different temperatures from 273 K to 1173 K separately. The surface morphology, surface concentration of the elements of the C-SiC coatings and element iron from substrate as well as their depth profiles were checked with SEM, XPS and SIMS analyses. The results show that the composition of the coatings is changed due to heat treatment at different temperatures. The C-50%SiC coating with an excellent hydrogen resistant property can act as hydrogen barrier at the temperature below 723 K. But the hydrogen resistant property of the coating becomes bad when it is used at the temperature of 1023 K.
