Rapid, large-scale isolation of human apolipoproteins A-I and A-II has been accomplished using two chromatographic procedures. The apolipoproteins adsorbed from plasma onto a column of phenyl-Sepharose are eluted with increasing propylene glycol concentrations. Apolipoproteins A-I and A-II can be resolved by elution with a linear 0 to 80% propylene glycol gradient. Homogeneous preparations of apo A-I and A-II are obtained following gel filtration in 3M guanidinium chloride.