Photocatalytic reduction of Cr(VI) to Cr(III) is one of the most promising technologies to remove Cr(VI) pollution because of its environmental friendliness, cost‐effective and energy saving. In this experiment, two‐dimensional Bi2MoO6(BMO) nanosheets and cerium‐based MOFs UiO‐66(Ce) were synthesized by solvent thermal method, and in the presence of BMO, the UiO/BMO‐x heterojunction composites were constructed in situ to explore its photocatalytic reduction properties of Cr(VI). The experiment showed that 4 mM of Cr (VI) solution could be reduced 100 % to Cr (VI) by 15 mg catalyst under optimal reaction conditions. The composite photocatalyst prepared in this experiment can realize the green treatment of Cr(VI) in the environment under photocatalytic conditions, and has potential application value in the remediation of heavy metal pollution.