High strength titanium alloy

The invention relates to a high strength titanium alloy, and in particular relates to a Ti-6Al-4.5Mo-3V-3Cr-2Sn series titanium alloy. The high strength titanium alloy aims at solving the problem of poor strength of extension and plasticity of the existing titanium alloy. The high strength titanium alloy comprises the following alloys in percentage by weight: 5.0%-7.0% of Al, 4%-6% of Mo, 2%-4% of V, 2%-4% of Cr, 1%-3% of Sn, and the balance of Ti and inevitable impurities. The strength of extension of the prepared titanium alloy after anneal is larger than or equal to 1100MPa, and the plasticity of the titanium alloy is larger than or equal to 15%, so that the high strength titanium alloy shows better strength of extension and plasticity.