Strain　rate　jump　tests　were　performed　on　the　Fe-Mn-Cu-C　TWIP　Steels　to　determine　thestrain　rate　sensitivity,　and　serrated　plastic　flow　was　observed　in　the　stress-strain　curves　duringtensile　tests　at　different　constant　strain　rates　ranging　from　2.5×10-4S-1　to　2.5×10-2S-1.　TheFe-Mn-Cu-C　TWIP　Steels　exhibit　high　work　hardening　rate　and　outstanding　mechanical　properties,The　excellent　mechanical　properties　are　attributed　to　dynamic　strain　aging(DSA)　effect,　whichresult　from　the　interaction　between　Mn(Cu)-C　atom　atmosphere,　C-vacancy,　C-C　pairs　and　movingdislocations.　©　(2013)　Trans　Tech　Publications,　Switzerland.