As a promising alternative to precious metal catalysts, Molybdenum carbide (MoC) still cannot compete with commercial Pt catalysts in many aspects. In the present work, we develop a simple carburization method to synthesize synergistic MoC catalysts with highly dispersed copper. Addition of copper could effectively induce formation of -phase of MoC and markedly improve electrochemical activity for HER reaction. When the doping ratio of Cu-Mo reaches 10:90, the Cu doped MoC displays the best catalytic performance, even compared with the commercial Pt/C catalyst. The enhanced HER activity for Cu-MoxCy can be attributed to the formation of active phase and also synergistic surface. [GRAPHICS] .