Polyunsaturated fatty acids of the omega-3 series, especially very long chain--eicosapenta- and docosahexaenoic acid (EPA, DHA)--exert a strongly desirable influence on health. However, their intake with the western-style diet is usually too low which favours development of many diseases (CVD, cancers, allergies, etc.). Nowadays elevation of EPA and DHA intake is commonly recommended, but almost the only dietary source of them is seafoods, especially fish. A new way to increase the intake of long-chain omega-3 without radical changes of eating patterns is enrichment of regularly consumed foods with unhydrogenated fish oil. The aim of this study was to establish sensory and nutritionally acceptable enrichment level of low-calorie spreadable fats (soft margarine and mix of butter and vegetable oil) with EPA and DHA by addition of fish oil preparations (ROPUFA--30% EPA, DHA and MARITEX--10%), and evaluation of the stability of enriched spreads during storage (sensory and chemical). It was shown that tested spreadable fats might be enriched up to 1% EPA, DHA (i.e. 3% ROPUFA, 8% MARITEX), and that this had no significant influence on sensory acceptability. Both used fish oils which exerted similar influence on the quality of fats. An enriched mix of butter and vegetable oil and margarine may be stored up to 3 and 6 weeks respectively without significant decrease of quality. Peroxide value and acid numbers were not much affected by enrichment and storage. Daily portion (25-30 g/day) of spreadable fats enriched on the level established in the study may provide 0.2-0.3 g EPA, DHA, significantly increasing the amount of long-chain omega-3 in the diet above those eaten normally.