Photocatalytic CO 2 reduction into syngas (CO and H 2 ) is one of sustainable strategies for recycling CO 2 into value-added products. Herein, a simple and effective two-step self-assembly process was developed to functionalize phosphorescent metal-organic framework (MOF) with single site catalyst. The resulting (Co/Ru) n -UiO-67(bpydc) supplied molecular platform to enable fast multielectron injection from photosensitizers (PSs) to Co-catalyst, leading to the first MOF-based composite photocatalyst for efficient syngas production with a yield of 13,600 μmol·g−1 (H 2 : CO = 2 : 1) in 16 h, 29.2-fold higher than that of its homogeneous counterpart. The H 2 /CO ratios can be well controlled by carefully adjusting the molar ratio of PS/catalyst in the MOF platform and the water content in the photocatalytic system. This work provides a prospective strategy for recycling CO 2 into H 2 -rich syngas by merging PSs and single-site catalysts into a MOF platform.