The development of electrocatalysts for hydrogen evolution reaction (HER) with high catalytic activity and stability in alk. medium remains a significant challenge.Herein, a catalyst (namely Zn0.05Ni3S2-P) was designed to achieve the excellent alk. HER performance owing to the boosted water dissociation and moderate H* adsorption energy.At the c.d. of 10 mA cm-2, the overpotential of Zn0.05Ni3S2-P is 143 mV.In addition, the Tafel slope and the charge transfer resistance of Zn0.05Ni3S2-P are reduced, and the electrochem. active surface area (ECSA) is expanded.D. functional theory (DFT) calculations show that the appropriate proportion of Ni to Zn optimizes the H* adsorption energy of the catalyst.The introduction of P cooperates with S to activate the water dissociation, reduce the H2O dissociation energy barrier, and accelerate the reaction kinetics.Moreover, in the process of electrolytic water splitting at 100 mA cm-2 c.d., the voltage is stable at 2.4 V, the hydrogen production rate is maintained at 1.84 mmol h-1, and the Faraday efficiency of hydrogen production is nearly 100 %.This work simultaneously considers the importance of water dissociation and H* adsorption energy in alk. HER, and provides a strategy for the design of highly active alk. HER catalysts.