The influences of chromium electroplating on hydrogen content, mechanical and fatigue properties of TC6 titanium alloy were studied by hydrogen testing equipment, tensile testing machine and fatigue testing machine. The results show that the hydrogen content of TC6 titanium alloy increased after chromium electroplating up to the top limit of the acceptance range. The hydrogen brittleness specimens made of TC6 were failure in the hydrogen embrittlement test. So these materials with chromium coating were not suggested to use for high stress concentration and load-carrying structure. The tensile strength of TC6 was kept constant. The elongation decreased by 17.3%, and section reduction decreased by 24.0%. The fatigue strength of TC6 after chromium electroplating decreased significantly from 626.0 MPa to 201.3 MPa by the tensile stress of chromium coatings.