This study was directed to define the taste compounds of crucian carp, Carassius caressius, free amino acids, nucleotides and their related compounds, organic bases, sugars, organic acids and minerals in the extracts of crucian carp were analyzed, and then followed by sensory evaluation of synthetic extracts prepared from 44 pure chemicals on the basis of the analytical data. Taste panel assessments of synthetic extracts prepared with each extractive component omitted were carried out by a triangle difference test, and changes in taste profile were assessed. In free amino acid composition, histidine was dominant occupying $46\%$ of the total free amino acids. The other abundant free amino acids were glycine, lysine, alanine and taurine. As for the nucleotides, IMP was dominant showing about $80\%$ of the total of nucleotides. The most abundant organic base was total creatinine. The content of betaine was poor and TMAO were trace in content. The main organic acids were succinic, propionic, butyric and valeric acid. Small amount of glucose, fructose and inositol were detected and ribose and arabinose were trace in content $K^+,;Na^+,;PO_4^{3-};and;Cl^-$ were found to be the major ions and small amount of $Ca^{++};and;Mg^{2+}$ were deleted. Judging from the results of omission test, the major components which contribute to produce the taste were serine, glutamic acid, lysine, arginine, tyrosine, phenylalanine, IMP, $Na^+,;K^+;and;PO_4^{3-}$.