Abstract The composition and the content of lipids, fatty acids and sterols during spawning (spring) in different tissues of herring Clupea harengus membras were compared with quantities of lipid compounds in abdomen muscle of brown shrimp Crangon crangon. The largest quantity of fatty acids in lipids (93.7%), was observed in fish muscle. The liver was characterized by a higher content and variety of sterols (about 4.6 times more than in fish muscle), and in fish sperm, additional fatty acids were identified and the highest amount of EPA and DHA (22% and 34% of fatty acids, respectively) was recorded. The brown shrimp, despite its small size, contained significantly more lipids than the Baltic herring per g of tissues. Fatty acids were at the same level (83% of the total lipids in shrimp muscle and 93.7% in fish muscle), but the amount of sterols was significantly higher in the muscle of shrimp (5.50 ±0.31 mg g−1, 17% of total sterols, n=10) than in fish muscle (1.33 ±0.04 mg g−1, 6.3% of total lipids, n=6). And thus, shrimp is a good source of food for higher trophic levels, and in consequence — a good source of PUFAs for humans. With these results we prove that shrimp and herring play an important role in the supply of EFAs, which has great pharmaceutical and medical benefits.