As photocatalysts, heterojunction materials have attracted much attention because of their capacity to integrate the promising performance of the individual components. Here, a series of heterojunction materials composed of silver cyanamide (Ag₂NCN) and graphitic carbon nitride (g-C₃N₄) have been fabricated using a facile grinding method. Upon photoexcitation, the heterojunction materials exhibited enhanced photocatalytic activity in the hydrogen evolution reaction (322.35 μmol g⁻¹ h⁻¹), 82.87 and 117.65 times higher than that of the pristine Ag₂NCN and g-C₃N₄, respectively. The photoelectrochemistry results revealed that the loading of Ag₂NCN onto g-C₃N₄ could be favorable to the photogenerated charge separation and transfer in the heterojuction system. In addition, the spent heterojuction retained a better photocatalytic activity after 30 hours recycling. Furthermore, the excellent synergetic effect between Ag₂NCN and g-C₃N₄ could achieve the effectively promoted separation of photogenerated electron–hole pairs, thus leading to the enhancement of photocatalytic performance under simulated sunlight illumination. This work could provide a general strategy to fabricate Ag-based materials on g-C₃N₄ photocatalysts with superior H₂ evolution performance.