Apolipoprotein E was isolated from human very low density lipoproteins by a two-step electrophoretic procedure derived from that of Méndez (1982. Anal. Biochem. 126: 403-408). It included separation in a sodium dodecylsulfate polyacrylamide slab gel, transfer into an agarose gel, and extraction by ultracentrifugation for 30 min. No protein labeling, dialysis, or concentration procedures were needed. The method was fast, showed an excellent protein recovery, and could be suitable as a general method of protein isolation by polyacrylamide gel electrophoresis.