Fatty acid compositions of seventy-two species of Korean fish muscle, 59 species of sea water fish and 13 species of fresh water fish, were studied. Polyunsaturated fatty acid (PUFA) was the richest fatty acid group in all fish samples, accounting for $38.0pm10.3\%$ of total fatty acids. Monounsaturated fatty acids $(MUFA,;31.4pm9.67\%)$ and saturated fatty acids $(SFA, 30.5pm3.81\%)$ showed a similar level. There was a positive correlation between the total lipid content and MUFA (r=0.7788, p<0.001) and a negative correlation between the total lipid content and PUFA (r= -0.7786, p<0.001) while there was no correlation between the total lipid content and SFA. The proportion of n-3 PUFA and n-6 PUFA was $29.7pm8.73\%$ and $6,48pm3.70\%$, respectively, in all fish samples. The n-3 PUFA was rich in sea water fish while n-6 PUFA was rich in fresh water fish. The migratory fish contained the highest level of the n-3 PUFA $(1.82pm1.01g/100g;muscle)$, followed by the fresh water fish $(1.09pm1.04g/100g;muscle)$, the reef fish $(0.90pm0.60g/100g;muscle)$ and the demersal fish $(0.77pm0.38g/100g;muscle)$. There was a positive correlation between the total lipid and n-3 PUFA content, $y=0.2083 imes+0.05 (r=0.9352,;p<0.0010)$