Titanium-silicon-nitrogen (Ti-Si-N) composites were produced from a mixture of Si3N4, titanium nitride (TiN), and titanium by spark plasma sintering to develop wear-resistant materials with good environmental and biological compatibilities in water and sea water. The Ti-Si-N composite consisted of Si3N4, TiN, and titanium metal-rich particles coated with TiSix. Results of sliding tests in water and in artificial sea water showed that the wear resistance of the Ti-Si-N composite was much better than that of the titanium metal.