Various TiO₂/ZnIn₂S₄ composites with an embedded structure have been developed by a facile one-pot synthesis. The activities of all samples were estimated by photocatalytic reduction of Cr(VI) under visible light (λ>420 nm). Results showed that the electrostatic interaction and self-assembly effect make TiO₂ nanoparticles inserting into ZnIn₂S₄ nanosheets. The resulting TiO₂/ZnIn₂S₄ composites show much better photocatalytic performance for Cr(VI) reduction than that of pristine TiO₂ and ZnIn₂S₄. Especially, the photocatalytic efficiency of T/ZIS-0.3 (TiO₂ loading of 30 wt%) is approximate 3 times as high as that of pristine ZnIn₂S₄ (TiO₂ exhibited almost no activity). The embedded structure of TiO₂/ZnIn₂S₄ offers apparent increase of specific surface area, visible-light absorption and electrons transfer efficiency, which are responsible for the boosted photocatalytic activity. This work would inspire researchers to construct high-efficiency semiconductor composites for photocatalytic environmental governance.