Consumption of fish is very beneficial to the health and development of the human body. They provide essential nutrients to the human. Fish oil contains higher amount of polyunsaturated fatty acids which have significant effect in maintaining a healthy cardiac life. Biochemical composition of boal (Wallago attu) was determined. It was found that fishes are rich sources of protein and other nutrients. Boal contain higher amount of moisture 77.51±0.35 (g%). All the other parameters such as, protein, lipid, total sugar and ash were 13.12±1.24 (g%), 1.94±0.06 (g%), 0.05±0.01 (g%), 1.55±0.05 (g%) in boal. Boal fish oil was extracted using n-hexane by soxhlet apparatus. The percentage of oil from boal fish powder was 18.24 (g% w/w). Lecithin was also extracted from this fish fleshes before and after oil extraction. Lecithin was 2.02 (g% w/w) and 3.68 (g% w/w) before and after oil extraction. The physicochemical properties of fish oil and lecithin were investigated. The saponification value, iodine value, acid value, peroxide value, percentage of free fatty acids of boal fish oil and lecithin were 199.27±0.78 (mg KOH/g), 129.67±0.63 (mg I/g), 16.78±0.01 (mg KOH/g), 11.65±0.15 (meq O2/kg), 8.43±0.09 (%). and 124.56±1.23 (mg KOH/g), 89.26±1.44 (mg I/g), 11.31±1.52 (mg KOH/g), 4.26±0.55 (meq O2/kg), 5.68±0.76 (%). The oxidative stability of boal fish lecithin was also measured. Boal fish lecithin showed higher oxidative stability due to the presence of natural antioxidant. Fatty acid composition of boal fish oil and lecithin was measured by gas chromatography (GC). The important polyunsaturated fatty acids eicosapentaenoic acid (EPA) and docosahexaenoic acid (DHA) were found to be 1.35% and 1.98%. But lecithin contains only 9% DHA and other monounsaturated fatty acids. This fish oil and lecithin also contain higher amount of monounsaturated fatty acid and average amount of polyunsaturated fatty acids. Therefore, we can use this fish oil and lecithin in edible purpose, food industry and pharmaceutical industry.