AbstractCatalytic water splitting is a promising approach to produce clean hydrogen fuel from renewable energy sources. However, developing hybrid heterostructures capable of efficiently breaking down water into its constituent elements, hydrogen, and oxygen, presents a considerable challenge. In this study, a novel hierarchical POM/Pd/MoS₂ hybrid heterostructure, composed of sheets of MoS₂ modified with Pd nanoparticles and combined with a cobalt‐based polyoxometalate (POM), serving as bifunctional catalyst for water splitting is reported. Through a synergistic synthetic approach, MoS₂, acting as a reducing agent, triggers the nucleation and growth of Pd nanoparticles, which, in turn, serve as anchoring sites for the polymerization of the cobalt‐based POM into fibers. POM/Pd/MoS₂ hybrid exhibits an enhanced oxygen evolution reaction (OER) activity, comparable to the benchmark catalysts Ir/C and IrO₂/C in alkaline media, being its hydrogen evolution reaction (HER) activity similar to the activated Pd/MoS₂ hybrid. The intriguing electrocatalytic capability of the resulting material for producing hydrogen and oxygen through electrochemical means arises from the enhanced charge storage capacity and conductivity of MoS₂, the multi‐electron transfer facilitated by the POM, and the high electrocatalytic activity of the metals.