Homogeneous noble metal catalysts used in alkene hydrosilylation reactions to manufacture organosilicon compounds commercially often suffer from difficulties in catalyst recovering and recycling, undesired disproportionation reactions, and energy-intensive purification of products. Herein, we report a heterogeneous 0.5Ruδ+/ZrO2 catalyst with partially charged single-atom Ru (0.5 wt.% Ru) supported on commercial ZrO2 nanocrystals synthesized by the simple impregnation method followed by H2 reduction. When used in the ethylene hydrosilylation with triethoxysilane to produce the desired ethyltriethoxysilane, 0.5Ruδ+/ZrO2 showed excellent catalytic performance with the maximum Ru atom utilization and good recyclability, even superior to homogeneous catalyst (RuCl3·H2O). Structural characterizations and density functional theory calculations reveal the atomic dispersion of the active Ru species and their unique electronic properties distinct from the homogeneous catalyst. The reaction route over this catalyst is supposed to follow the typical Chalk—Harrod mechanism. This highly efficient and supported single-atom Ru catalyst has the potential to replace the current homogeneous catalyst for a greener hydrosilylation industry.