High-performance catalysts for electrocatalytic and photoelectrochemical water splitting hold great promise for renewable energy conversion and storage. Herein, using porous N-doped carbon supported Au nanoparticles as catalysts, we demonstrate that the photon-induced localized surface plasmon resonance (LSPR) excitation on Au nanoparticles dramatically improves the hydrogen evolution reaction (HER), leading to a more than 4-fold increase of current and meanwhile affording a markedly decreased overpotential of 99 mV at a current density of 10 mA cm⁻². The HER enhancement can be largely attributed to the efficient charge transfer of N-doped carbon that fastens the injection of hot electrons from plasmonic Au nanoparticles. This study highlights the increase of HER catalysis efficiency by plasmonic excitation and could provide new avenues towards the design of higher energy conversion catalytic water splitting systems with the assistance of light energy.