In this report, silver chromate (Ag2CrO4) nanoparticles with small size were highly loaded on the g-C3N4 by a simple hydrothermal method to making the heterostructure photocatalysts. The synthesized photocatalysts were characterized by XRD, BET, FESEM, FTIR, PL and UV–vis DRS. The photocatalytic activity of these samples was measured in proportion to the amount of degradation of the Cr(VI) and 2NP pollutants with the illumination of visible light. Fairest, 10% Ag2CrO4 loaded g-C3N4 photocatalyst show high photodegradation efficiency (97%) towards 2NP than compared with pristine Ag2CrO4 (58%) and g-C3N4 (43%). The constructed Ag2CrO4/g-C3N4 architecture of a S-scheme framework can stimulate the photocatalytic production by enlightening the ability to redox, promoting light absorption and assist the division of charges. The specific S-scheme framework and outstanding photocatalytic performance indicated this heterostructure photocatalysts could serve as a useful tool for the practical environmental applications. Moreover, the mechanism of S-scheme electron transfer path was proved by density functional theory (DFT) calculation.