Studies　were　made　on　the　symmetric　tensile-compressive　low　cycle　fatigue　behavior　and　the　influence　of　dynamic　strain　aging　(DSA)　pre-treatment　of　18-8　austenitic　stainless　steel.　Within　the　testing　amplitude　range　of　strain　±0.5%　to　±1.5%,　the　three　processes　of　cyclic　hardening,　cyclic　saturation　and　cyclic　softening　were　observed.　In　the　same　amplitude　of　strain,　the　peak　stress　of　the　samples　pre-treated　by　DSA　is　higher　than　that　of　solid-solution　and　cold　working　pre-treatment,　but　no　remarkable　differences　of　the　fatigue　lives　of　them　were　found.　The　TEM　observation　showed　that　the　uniform　and　stable　dislocation　networks　with　high　density　form　after　DSA　pre-treatment,　which　increases　the　cyclic　peak　stress.　The　cyclic　softening　results　from　the　low　dislocation　density　and　elongated　cell　structure　with　low　energy.