<p>Photocatalytic hydrogen evolution reaction (HER) from pure water is a promising strategy to address critical challenges in energy sustainability and environmental remediation. However, HER over single-component photocatalysts is intrinsically limited by inefficient carrier separation and relatively poor photostability. Forming abundant interfaces between two components is an effective approach for solving these issues. Herein, a series of hierarchical core-shell heterojunction photocatalysts, designated as F@Z-<i>X</i>, was rationally constructed by <i>in situ</i> growing ZnIn₂S₄ (ZIS) nanosheets on a Ti-based metal-organic framework (FIR-125), demonstrating remarkable structural stability. Due to the abundant intimate contact interfaces and well-matched band structure, the F@Z-<i>X</i> series exhibit enhanced HER performance. Among them, the optimized heterojunction F@Z-0.25 shows a photocatalytic hydrogen evolution rate of 3789.45 µmol g⁻¹ h⁻¹, which is about 4.4 and 264.4 times higher than that of pristine ZIS (859.57 µmol g⁻¹ h⁻¹) and FIR-125 (15.32 µmol g⁻¹ h⁻¹), respectively. Moreover, the photocatalyst manifests excellent reusability and durability, maintaining its performance over five consecutive cycles and sixteen hours of continuous reaction. The outstanding performance of F@Z-0.25 may be ascribed to an optimal balance among three fundamental photocatalytic processes: sufficient light absorption, exceptional carrier separation, and appropriate surface reaction. This work offers valuable insights into the rational design and controllable synthesis of novel heterojunction photocatalysts for efficient hydrogen evolution.</p>