Hydrogen production by water electrolysis is regarded as an ideal solution to the escalating global energy crisis and environmental pollution due to its high purity, cleanliness, and compatibility with photovoltaic and wind power. However, the overall water splitting electrocatalysts of low-cost, highly active, and durable for using in alkaline media remains a considerable challenge. In this study, a three-dimensional Ni3S2/CeO2@NF heterostructured catalytic electrode was synthesized using a two-step hydrothermal method, with its phase, morphology, and structure systematically characterized through XRD, XPS, SEM, and TEM analyses. The HER and OER performances of Ni3S2/CeO2@NF were evaluated in 1 M KOH solution, revealing that the strong interfacial synergy between Ni3S2 and CeO2 significantly enhances electron transfer capabilities, resulting in high catalytic activity for both HER and OER. Utilizing Ni3S2/CeO2@NF as both the cathode and anode in an electrolytic cell achieved a current density of 10 mA/cm2 at