A wet‐incipient impregnation method was reported to synthesize hierarchical porous bimetallic (Co, Zn)‐zeolitic imidazolate frameworks (ZIF‐8)/TiO2 (Co@ZIF‐8/TiO2) for green hydrogen generation via photocatalytic water splitting. Co@ZIF‐8/TiO2 showed higher photocatalytic efficiency than TiO2, with a hydrogen generation rate (HGR) of 13 mmol·h−1·g−1 with a 151‐fold increase in the catalytic performance of TiO2. The photocatalytic HGR of Co@ZIF‐8/TiO2 was superior to that of the ZIF‐8/TiO2 heterostructure. Co@ZIF‐8 showed a hierarchical porous structure containing micropores and mesopores regimes, providing a proficient transport channel for charge transfer. This study presents new prospects for using hierarchical porous metal–organic frameworks (MOFs) as support and promoter in photocatalytic applications of semiconductor such as TiO2.