To　investigate　the　fatigue　performance　of　recycled　aggregate　concrete　and　the　effect　of　silica　fume,　flexural　fatigue　tests　of　natural　aggregate　concrete　(NAC),　recycled　aggregate　concrete　(RAC)　and　silica　fume　recycled　aggregate　concrete　(RAC-SF)　were　carried　out　at　three　stress　levels.　The　Weibull　distribution　and　the　probability　equation　of　flexural　fatigue　life　were　established　and　analysed.　Furthermore,　the　relationship　between　interface　transition　zone　(ITZ)　and　its　effects　on　flexural　fatigue　performance　were　studied　by　using　nano-indentation.　The　results　show　that　the　flexural　fatigue　life　of　RAC　follows　two-parameters　Weibull　distribution　and　the　double-logarithmic　fatigue　equation　could　be　fitted　by　Weibull　parameters.　Compared　with　NAC,　RAC　has　larger　thickness　and　smaller　indentation　modulus　of　the　multiple　ITZs,　which　facilitates　the　derivation　and　development　of　cracks,　accounting　for　the　lower　flexural　fatigue　life　of　RAC　than　that　of　NAC　at　the　same　stress　level.　The　addition　of　silica　fume　to　RAC　results　in　the　reduction　of　thickness　of　multi　ITZs,　and　the　increasing　of　indentation　modulus　of　multi　ITZs　and　new　mortar.　Moreover,　the　resistance　to　fatigue　damage　is　enhanced　and　the　flexural　fatigue　performance　of　RAC　is　improved,　which　consequently　prolongs　the　service　life　of　RAC.　©　2022,　Editorial　Office　of　Journal　of　Building　Structures.　All　right　reserved.