It has been investigated the influence of multi-walled nanotubes on the properties of two types siliconized graphites, namely SGP-0,5 and SGP-0,1. It has been shown that multi-walled nanotubes have higher capability to form silicon carbide with silicon in comparison with natural graphite. It facilitates to improve the properties of siliconized graphites even with small additives of multi-walled nanotubes. The carbide carbon-silicon materials producible now in Russia demand the further researches and technological developments in connection with change of raw-material base of carbon material production on which basis the siliconezed graphites are produces, and also the new requirements specified to modern generations of composite materials.