Synthesizing composites is one of the most effective ways to reduce the recombination probability of electron?hole pairs and to improve photocatalytic activity. In this study, our research group first combined reduced graphene oxide (rGO) with porous graphitic carbon nitride (pg-C3N4) to form pg-C3N4@rGO core-shell, and then loaded bismuth tungstate (Bi2WO6) onto the pg-C3N4@rGO to acquire a ternary composite catalyst. The results of the experiment show that, the ternary photocatalyst exhibited better phototalytic performance than pure pg-C3N4 and Bi2WO6. When the weight radio of pg-C3N4@rGO and Bi2WO6 was 100:8, the ternary photocatalyst showed the best photocatalytic performance. Its photocatalytic kinetic constant reached 68 ? 10?4 min?1, which was 13.6 times that of pg-C3N4 and 7.6 times that of Bi2WO6. The photocatalytic performance was boosted by the heterojunction structure of the ternary composite, which can effectively separate electron?hole pairs rapidly, and thereby increased quantum yield, thus improving the photocatalytic performance.