This　paper　focuses　on　the　fatigue　time-dependent　reliability　of　CRTS　Ⅱ　track　slabs　on　bridges　considering　prestress　losses　under　the　most　adverse　loads.　Specifically,　we　establish　the　limit　state　functions　of　six　single　failure　modes:　longitudinal　and　transverse　concrete　tension,　concrete　compression,　and　steel　bending　and　tension,　and　multiple　failure　modes　under　the　combined　effects　of　train　load,　temperature　gradient　and　bridge　deformation;　explore　the　effects　of　train　load,　temperature　gradient　and　bridge　deformation　and　determine　the　most　unfavorable　load　cases;　analyze　the　statistical　characteristics　of　random　parameters　The　PHI2　time-dependent　method　is　applied　to　analyze　the　fatigue　time-dependent　reliability　of　the　track　slab　over　a　60-year　service　period,　and　a　comparative　study　is　made　with　the　loss　of　prestress　without　consideration;　the　influence　of　different　values　of　the　expansion　factor　on　the　reliability　index　is　studied　and　an　error　analysis　is　made.　It　is　found　that:　during　the　service　life　of　the　track　slab,　the　longitudinal　and　transverse　concrete　compression,　bending　and　tensile　reinforcement　and　fatigue　time-dependent　reliability　indexes　of　the　track　slab　system　meet　the　specification　requirements;　the　longitudinal　concrete　of　the　track　slab　is　bound　to　crack　in　tension　and　the　transverse　concrete　is　more　likely　to　crack　in　tension;　the　reliability　indexes　obtained　without　considering　the　prestress　loss　are　small,　which　makes　the　calculation　results　conservative　and　causes　waste　of　human　and　material　resources.　Different　expansion　coefficients　will　bring　some　errors　to　the　reliability　index,　but　the　reliability　index　values　all　meet　the　specification　requirements.　The　research　results　can　provide　theoretical　reference　for　the　maintenance　and　repair　of　CRTS　Ⅱ　type　track　plate.　©　Geology　Resource　Management　and　Sustainable　Development　2022.All　rights　reserved.