LC-MS/MS was used to determine the amino acid composition in muscle, ovary and liver of whiting, Merlangus merlangus euxinus, caught off the coast of Sinop province in the Black Sea. A total of 19 amino acids (AA) were found in the different samples. The essential amino acids (EAA) in the different tissues of whiting were 55.9% in the meat, 54.8% in the ovary and 51.7% in the liver of the total amino acids.