Photoelectrochemical conversion of glycerol into high-value dihydroxyacetone offers a sustainable approach via BiVO4, which manifests highly photoactive properties, but poor charge transport ability. Herein, we fabricated N2-annealed BiVO¬4 through a simple spin-coating method and N2 annealing process. The effect of N2 treatment did not significantly impact the surficial catalytic efficiency, while the bulk efficiency was increased, resulting from changes in oxygen vacancy concentration and carrier density. Owing to simultaneous improvement in bulk electron-hole separation efficiency, N2-annealed BiVO4 at 150 ℃ exhibited an enhanced photoelectrochemical dihydroxyacetone production rate of 160 mmol m-2 h-1 at 1.0 V vs. RHE, which was about more than 2 times higher than pristine BiVO4. This work not only makes biodiesel production more profitable and sustainable but also achieves advanced production of dihydroxyacetone.