Fatigue　life　of　reference　RC　beams　(N-u)　and　residual　fatigue　life　of　RC　beams　after　pre-fatigue　loading　(0.01-1.2　million　cycles,　similar　to　0.2%　similar　to　30%N-u)　and　chloride　exposure　(3,　6　months)　in　sequence,　were　tested.　Fatigue　behaviors　significantly　degrade　at　the　pre-fatigue　cycles　of　1%　to　30%N-u,　where　obvious　degradations　are　shown　as　the　pre-fatigue　cycles　increase　to　10%N-u.　Fatigue　life　of　corroded　and　un-corroded　beams　can　be　modeled　by　the　two-parameter　Weibull　distribution　at　a　given　load　level,　and　hence　a　reliability　assessment　method　is　proposed　to　give　the　minimum　safety　fatigue　life　of　RC　structures　with　chloride　exposure.