• Novel MOF-derived CdIn 2 S 4 @A/R-TiO 2 and CdIn 2 S 4 @TiO 2 with 2D/3D core–shell heterostructures were synthesized. • As-prepared photocatalysts showed excellent photocatalytic activity for degrading typical organic contaminants and hydrogen production. • Reaction rate of CdIn 2 S 4 @A/R-TiO 2 (Ⅱ-scheme mechanism) was higher than that of CdIn2S4@TiO2 (Z-scheme mechanism). • Synergy between electron acceptor of A/R-TiO 2 and CdIn 2 S 4 was discussed and the transition path of photoexcited electrons was proposed. Two-dimensional (2D) disk-like shape titanium oxide with controllable phase was prepared using NH 2 -MIL-125(Ti) as template by pyrolysis at different atmospheres process to acquire TiO 2 (3.09 eV, air) and A/R-TiO 2 (2.81 eV, N 2 ). Subsequently, 2D/3D core–shell heterostructures (CdIn 2 S 4 @TiO 2 and CdIn 2 S 4 @A/R-TiO 2 ) were built by in-situ self-assembly tactics. Characterization displayed that the 3D CdIn 2 S 4 shell with diameter 5.5 μm was uniformly wrapped on the surface of 2D A/R-TiO 2 and TiO 2 core with 3 μm. Compared with CdIn 2 S 4 @TiO 2 (74.27 m 2 /g), the CdIn 2 S 4 @A/R-TiO 2 possessed higher BET surface area (106.54 m 2 /g), providing larger contact areas and exposed more active sites. And CdIn 2 S 4 @A/R-TiO 2 -1.2 showed the best photocatalytic degradation and hydrogen production, which was much higher than that of CdIn 2 S 4 @TiO 2 -0.8. The mechanism of the proposed photocatalysis is further discussed: the CdIn 2 S 4 @TiO 2 followed the Z-scheme mechanism while the Ti 3+ and Ti 4+ redox sites generated in A/R-TiO 2 could be mutually transformed in situ and CdIn 2 S 4 @A/R-TiO 2 -1.2 followed the Ⅱ-scheme mechanism.