Achievement of an efficient and stable electrocatalytic glycerol oxidation reaction (EGOR) is limited by a lack of strategies for designing advanced electrocatalysts that satisfy the desired product selectivity, high electro-catalytic activity, and stability. Here, we report that the reaction pathway of EGOR can be modulated by the incorporation of amorphous antimony oxide (SbOx) on the surface of a Pt nanoparticle electrocatalyst (SbOx-Pt), which creates highly selective glycerol oxidation to dihydroxyacetone (DHA), one of the most valuable products of EGOR. The selective control of adsorption behaviors of glycerol oxidation products allows for SbOx to act as a reaction pathway modulator. Moreover, SbOx deposition on a Pt surface also enhances the stability, electro-catalytic activity, and glycerol conversion of the Pt electrocatalyst, and thus promotes the EGOR. As a result, the SbOx-Pt electrocatalyst achieves a high DHA selectivity of 81.1%, which is about 11 times higher than that of commercial Pt/C electrocatalysts.