Developing an accessible and durable catalyst with minimal overpotentials to split water to produce both H2 and O2 is challenging. The hydrothermal-deposition precipitation route was adopted to synthesize α-Ag2WO4 (20–80%) supported on α-Mn3O4 (AgW/Mn). The 60%AgW/Mn catalyst, which is structurally made up of Mn platelets decorated with AgW nanoparticles, confirmed the existence of the MnO2 (200) active sites, surpassing the Ag nanoparticles (54.3%), and the proportion of the birnessite Mn3+/4+ moieties. In comparison to other catalysts, it presented more selectivity for OER in 1.0 M KOH with a low overpotential (0.28 V) at 10 mA cm -2, a Tafel slope of 50.7 mV dec-1, an O2-equivelent amount of 221.5 mmolg- 1, and a TOF of 1.17 s- 1. Similarly, it produced HER at an overpotential of 0.089 V at η10, a Tafel slope of 73.35 mV dec -1, an H2-generated amount of 429.4 mmol g -1, and a TOF of 1.59 s-1.