Cu-5% Cr alloy bulk material with submicron grains were fabricated by mechanical alloying and subsequent hot hydrostatic extrusion. The microstructure, mechanical properties and electrical conductivity of the alloy were experimentally investigated, and the influence of the extrusion temperature on its microstructure and properties was made clear. Also, the strengthening mechanism of the alloy was discussed. It was revealed that the microstructure of the alloy is very fine, with an average grain size being about 100 similar to 120 nm, and thus possesses significant fine-grain strengthening effect, leading to very high mechanical strength of 800 similar to 1000 MPa. Meanwhile, the alloy also possesses quite good electrical conductivity and moderate tensile elongation, with the former in the range of 55% similar to 70% (IACS) and the latter about 5% respectively.