A surface carburization technique of medical titanium alloy femoral head in total hip arthroplasty comprises subjecting medical titanium alloy TC4 to surface carburization by using acetylene as carburizing agent to carry out gaseous carburization at high temperature to give medical titanium alloy femoral head in total hip arthroplasty with TiC ceramic on surface thereof. The TiC ceramic layer on femoral head can be more than 100 micron thick, which is relatively thick, overcomes the disadvantages in available medical titanium alloy material, and is particularly useful for replacement of total hip or knee arthroplasty.