Omega-3 long-chain polyunsaturated fatty acids (ω-3 LCPUFA) eicosapentaenoic acid (EPA) and docosahexae-noic acid (DHA) are found in significant amounts in fatty fish (tuna fish, mackerel and salmon) and especially in the oil obtained from these species, which is actually utilized as a nutritional supplement (nutraceutical). After ingestion, both EPA and DHA are rapidly incorporated into cellular membrane phospholipids where they can be released by lipooxygenases and cyclooxygenases enzymes and transformed in powerful bioactive products wich have cytoprotective and especially anti-inflammatory activities. Clinical and epidemiological evidence have firmly established that consumption ofEPA and DHA may contribute to the prevention and / or treatment of a number of diseases, especially those where inflammation plays a remarkable role in its development. EPA and DHA exhibit potent anti-inflammatory properties, either via the generation of anti-inflammatory products, such as the resol-vins, or by blocking inflammatory agents. In the present paper we review possible clinical applications of EPA and DHA in pathologies, such as cardiovascular and neurodegenerative diseases, cancer, inflammatory bowel disease, rheumatoid arthritis and ischemia - reperfusion injury. The evidence suggests that ω-3 LCPUFA may have promising applications in the prevention and / or treatment of different clinical and nutritional pathologies.