Fish lipids are the main sources of a special type of fatty acids, known as omega 3 type polyunsaturated fatty acids, recognized as an important pharmaceutical drug to prevent a number of coronary heart diseases. Some of the fatty acids are essential fatty acids in all diets. The lipid content and fatty acid profile of 20 very common fish species were analysed by gas chromatography. The lipid content was found to vary over a wide range (0.5 - 15% on wet basis), but most species contained less than 10%. The most abundant fatty acids in the fish examined were palmitic (C 16:0), oleic (C 18:1), eicosapentaenoic (C 20:5 n-3, EPA) and docosahexaenoic (C 22:6 n-3, DHA). Most small pelagics contained high levels (around 30% of total fatty acids) of omega 3 polyunsaturated fatty acids (omega 3 PUFA). Among these species, the highest amounts of omega 3 PUFA were present in Yellowstripe scad (Selaroides leptolepis (Suraparawa)), Dorab-wolf herring (Chirocentrus dorab (Katuwalla)), Spotted sardinella (Amblygaster sirm (Hurulla)), Blacktip sardinella (Sardinella melannura (Salaya)), Toothpony (Cassa minita (Mas karalla)), White sardinella (Sardinella albella (Sudaya)) and these levels were 34.4, 33.9, 32.3, 32, 31.3 and 30.4% respectively. The lowest level of omega 3 PUFA, 7.1%, was reported in Silver sillago (Sillago sihama (Kalanda)). In most species studied, the total amount of omega 3 PUFA contributed for around 90% of the total PUFAs. The two most important omega 3 PUFAs, namely EPA and DHA contributed for nearly 85% of the total omega 3 PUFAs.