The phycocyanin (PC) is a kind of fluorescence molecular probe because it has characteristic absorption spectra and fluorescence spectra.To get highly purified phycocyanin,the successive procedure of column chromatography was set up with SephadexG-200、DEAE-SephadexG-25、HA、and SephadexG-200.The results showed that the purity standral (ratio of A₆₁₅／A₂₈₀) reaches to 14 at pH 7.0,and it has been demonstrated by PAGE as a single band.