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　0.5Ru(delta+)/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　H-2　reduction.　When　used　in　the　ethylene　hydrosilylation　with　triethoxysilane　to　produce　the　desired　ethyltriethoxysilane,　0.5Ru(delta+)/ZrO2　showed　excellent　catalytic　performance　with　the　maximum　Ru　atom　utilization　and　good　recyclability,　even　superior　to　homogeneous　catalyst　(RuCl3　center　dot　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.