Abstract:(TiC+TiB)/Ti6Al4V composites with different TiC and TiB contents were prepared by in situ synthesis. The influence of load on dry sliding friction and wear performance of in-situ (TiC+TiB)/Ti6Al4V composites (designated as TMC) was studied by HT-1000 friction and wear testing machine, and the wear behaviors of the composites were also investigated by scanning electron microscopy (SEM) and Bruker 3D profilometer. The results show that the wear resistance of TMC was improved by the formation of TiC and TiB phases compared with Ti6Al4V matrix. For the composites with different volume fraction reinforcing phases, the wear rate and wear depth were increased with the increasing of the applied load, and the friction coefficient decreased and fluctuated within a small range. At low loads, the worn surface was covered with grooves and a small amount of wear debris; under heavy loads, the worn surface was covered with narrow and shallow grooves and large amount of wear debris. Wear mechanisms were abrasive wear and oxidation wear. With the increasing of the load, the size of the debris was increased.