Extn. of waste fish oil with supercrit. CO2 under pressure of 150 and 200 bar at 60 degrees C was carried out. Two product sepn. stages were used: first one at 80, 100 or 120 bar and second one at approx. 52 bar. Significant changes in the fatty acid content compared to the raw material were obsd. in the product obtained from the extn. at 200 bar and sepd. at 100 bar. The erucic acid content increased three-fold in the product.