Recycled　aggregate　concrete　(RAC)　is　modified　by　nano-silica　to　study　the　fatigue　behavior　due　to　uniaxial　compressive　repeated　loading.　Considering　the　recycled　aggregate　replacement　rate　as　the　main　parameter,　the　fatigue　life,　fatigue　equation,　fatigue　deformation　law　and　residual　stress　of　RAC　are　recorded　and　analyzed.　Microscopically,　the　influence　of　nano-silica　on　multiple　interface　transition　zones　of　RAC　is　discussed　based　on　nanoindentation.　The　results　show　that　the　fatigue　life　of　each　group　well　obeys　the　two-parameter　Weibull　probability　distribution.　Under　50%　guarantee　rate　and　0.75　stress　level,　the　fatigue　life　of　RAC　with　100%　recycled　coarse　aggregates　is　25.8%　lower　than　that　of　ordinary　concrete.　The　incorporation　of　nano-silica　improves　the　fatigue　life　of　RAC　significantly.　Compared　with　other　test　group　through　the　strain　evolution　curve　and　the　residual　stress　model,　the　residual　strength　attenuation　nonlinearity　is　obvious　for　RAC　incorporating　nano-silica.　Nano-silica　improves　the　indentation　modulus　of　the　multiple　interface　transition　zones,　which　is　the　reason　for　the　improvement　of　the　fatigue　behavior　of　RAC.　©　2021,　Engineering　Mechanics　Press.　All　right　reserved.