Abstract: Factor analysis and system clustering were used to study the classification of mirror carps in different seasons based on body parameters and nutritional composition in their back and abdominal muscles. The results showed that the major body characteristics of mirror carps in spring and summer exhibited larger bodies, higher proportion of viscera and lower proportion of skin; in contrast, mirror carps in autumn and winter had smaller bodies, lower proportion of scale and viscera, and higher proportion of fish muscle. The major nutritional characteristics of abdominal muscle from mirror carps in spring and summer revealed lower contents of proteins, free amino acids and ash, and higher content of water; the major nutritional characteristics of abdominal muscle from mirror carps in autumn had higher contents of proteins and ash, and lower content of water; the major nutritional characteristics of abdominal muscle from mirror carps in winter had higher contents of proteins, crude fat and total sugar, and lower content of water. The major nutritional characteristics of back muscle from mirror carps in spring revealed the lower contents of proteins, crude fat, total sugar and ash, and higher contents of free amino acids and water; the major nutritional characteristics of back muscle from mirror carps in summer had lower contents of crude fat and total sugar, and lower contents of free amino acids, ash and water; the major nutritional characteristics of back muscle from mirror carps in autumn and winter had lower contents of crude fat, total sugar and water, and higher contents of proteins, free amino acids and ash.

Key words: Cyprinus carpio var. specularis, body characteristics, nutrient, factor analysis, system clustering