Exploring bifunctional electrocatalysts with high-efficiency and stability toward overall water splitting is desirable for sustainable energy technologies, yet challenging. Herein, we report the construction of Ni₃N on the surface of Ni-MOF-74 through an in-situ nitriding process. The obtained Ni-MOF-74/Ni₃N exhibits remarkable HER activity, with an overpotential of 73 mV to deliver 10 mA cm⁻². Theoretical calculations and experimental study demonstrate the electron transport between Ni₃N and Ni-MOF-74, leading to the improved H₂O adsorption, optimized hydrogen adsorption, and increased H_ad diffusion, which contributes to the enhanced HER performance. Besides, the obtained Ni-MOF-74/Ni₃N also possesses outstanding activity toward OER and overall water splitting.