Abstract: The biochemical compo sition of muscle were examed in six pelagic fishes( Decapterus maruadsi , Sardinella aurita, Pneurmatophorus japonicus , Decapterus lajang , Trachurus japonicus , Rastrelliger kanagurta) . The protein content of muscle is 16. 94% - 18. 77%, the lipid content is 20. 12% - 25. 15%. With the increase of body length, lipid content increases. There is apparently relationship between the lipid content of muscle and reproduct ive activities. 17 amino acids in muscle were detected, the percentage of the essential amino acids in total amino acids content s is 45. 25%- 49. 39% , the polar amino acids, nonpolar amino acids and tasty amino acids in muscle are 16%, 39. 24%- 41. 59%, 42. 56%- 46. 02% respectively.