A　rapid,　simple　and　sensitive　method　was　developed　to　characterize　S.　aureus　in　exponential　phase　by　a　high　performance　ion-exchange　chromatograph　equipped　with　a　laser　light-scattering　detector.　An　ion-exchange　column　(TSKgel　SuperQ-TOYOPEARL　650C　column,　7.6　mm　i.　d.　×　100　mm,　Tosoh,　Japan)　was　used　for　the　separation.　The　mobile　phase　was　a　20　mmol/L　piperazine-　hydrochloric　acid　(pH　6.0)　buffer.　It　was　found　that　S.　aureus　in　exponential　phase　exhibited　two　elution　peaks.　Transmission　electron　microscope　(TEM)　showed　that　the　bacterial　cells　in　the　first　peak　appeared　to　be　circular,　while　the　cells　in　the　second　one　appeared　to　be　elliptical　and　had　one　obvious　diaphragm.　It　is　found　that　the　proliferation　capability　of　the　second　fraction　was　better　than　the　first　fraction　by　65.　3%.　These　results　suggested　that　the　first　fraction　was　the　S.　aureus　that　stopped　dividing,　while　the　second　one　was　the　S.　aureus　that　were　undergoing　cell　division.　Therefore,　the　chromatographic　method　developed　here　may　be　a　promising　tool　for　the　rapid　and　efficient　separation　and　characterization　of　bacterial　cells.