The effects of pulsed electric fields(PEF) on the structures of intracellular proteins of E.coli were investigated by SDS-PAGE analysis and FTIR.The original spectrum was dissolved by Fourier self-deconvolution and curve-fitting to show the peaks of the α-helix,β-turn,random coil and β-sheet in combination with CD spectrum.The results showed PEF treatments(30 kV/cm,400μs)can induce the formation of aggregates.The contents of β-sheet decreased from 45.40% to 21.50% and the contents of β-turn decreased from 23.80% to 8.81%,while the contents of random coil increased from 0.13% to 36.95%.The contents of α-helix changes insignificantly.