We have synthesized a porous Mo‐based composite obtained from a polyoxometalate‐based metal–organic framework and graphene oxide (POMOFs/GO) using a simple one‐pot method. The MoO2@PC‐RGO hybrid material derived from the POMOFs/GO composite is prepared at a relatively low carbonization temperature, which presents a superior activity for the hydrogen‐evolution reaction (HER) in acidic media owing to the synergistic effects among highly dispersive MoO2 particles, phosphorus‐doped porous carbon, and RGO substrates. MoO2@PC‐RGO exhibits a very positive onset potential close to that of 20 % Pt/C, low Tafel slope of 41 mV dec−1, high exchange current density of 4.8×10−4 A cm−2, and remarkable long‐term cycle stability. It is one of the best high‐performance catalysts among the reported nonprecious metal catalysts for HER to date. Nanocomposite catalyst: A novel Mo‐based catalyst for the hydrogen‐evolution reaction has been synthesized by directly carbonizing a composite obtained from polyoxometalate‐based metal–organic frameworks and graphene oxide at a relatively low temperature. The Mo‐based catalyst exhibits a positive onset potential, low Tafel slope, high exchange current density, and long‐term stability for the hydrogen‐evolution reaction in acidic media.