Under　the　actions　of　train　load　and　temperature,　several　serviceability　failure　modes　of　the　China　Railway　Track　System　(CRTS)　Ⅱ　track　slab　exist　such　as　excessive　longitudinal　crack　width,　lateral　cracking,　and　deformation.　In　this　study,　the　system　reliability　of　CRTS　Ⅱ　track　slab　under　the　serviceability　limit　state　was　investigated　considering　serviceability　failure　modes.　The　individual　performance　functions　corresponding　to　these　serviceability　failure　modes　were　firstly　investigated,　based　on　which　the　system　limit　state　function　of　the　track　slab　was　constructed.　Then,　using　method　of　moments,　the　system　reliability　of　the　track　slab　was　analyzed,　and　the　result　was　compared　with　the　reliabilities　of　individual　failure　modes.　Ultimately,　the　influence　of　temperature　on　the　system　reliability　was　investigated　by　sensitivity　analysis.　The　results　indicate　that　the　system　reliability　of　the　track　slab　under　the　serviceability　limit　state　is　at　a　relatively　high　level　when　the　mean　values　of　temperature　gradient　and　axial　temperature　are　not　negative　simultaneously;　as　the　reliability　of　the　track　slab　will　be　overestimated　by　the　independent　reliability　analysis　of　individual　failure　modes,　it　is　necessary　to　conduct　system　reliability　analysis　of　the　CRTS　Ⅱ　track　slab;　the　system　reliability　of　the　track　slab　is　significantly　affected　by　temperature　gradient　and　axial　temperature.　©　2022,　Department　of　Journal　of　the　China　Railway　Society.　All　right　reserved.