Gel permeation chromatography was found to be an efficient and reproducible technique for removing lipids from fish extracts. Recoveries of DDT, DDD, DDE, methoxychlor, lindane, dieldrin, endrin, malathion, and parathion were found to be greater than 95%. Pesticide concentrations were equivalent to 0.01-1.0 ppm, based on the original fish tissue. Pesticide analysis was by gas chromatography, using an electron capture detector, and by liquid scintillation. Less than 0.5% of the lipids originally present in the fish extract was recovered in the pesticide-containing eluate. Several solvent and lipophilic gel systems were evaluated. A chromatographic system using cyclohexane and Bio Beads S-X2 gave the most satisfactory separations. Polychlorinated biphenyls were also recovered in good yields. When this technique was used in conjunction with the polychlorinated biphenyl separation technique of Armour and Burke, excellent results were obtained. The system, as described, may be adapted for automatic sample cleanup and may be used as the sole cleanup technique with some samples.