Bimetallic AgCo/g-C3N4 photocatalysts were successfully prepared by a facile chemical reduction method and used to investigate their photocatalytic H2 production performance. Bimetallic AgCo as a cocatalyst can be well matched with g-C3N4, which is beneficial for increasing the number of active reaction sites and narrowing the band gap. A possible photocatalytic mechanism was explored by XRD, FTIR, SEM, TEM, UV–vis DRS, BET, and PL characterization. The photocatalytic H2 production activity of the optimal 5%AgCo/g-C3N4 photocatalyst reached 12994.2 μmoL/g, which was 54.7 times higher than g-C3N4. Owing to the close interfacial contact between bimetallic AgCo and g-C3N4, the transfer distance was shortened, and the photogenerated electron and hole pairs were effectively separated. This study provides a new strategy for the synthesis of excellent H2 production photocatalysts using bimetallic nanoparticles.