Excessive lipid accumulation in hepatopancreas of grass carp is very common under high density and mixed cultivation.To explore the biochemical mechanism of excessive lipid accumulation in hepatopancreas and promote the healthy cultivation of grass carp,metabonomics analysis of hepatopancreas and serum of grass carp based on ¹H-NMR and hepatopancreas lipid were carried out.Grass carp were classified into normal hepatopancreas lipid(3% to 4%)group and excessive hepatopancreas lipid(14%-16%)group.The results indicated that 58 and 47 metabolites were detected in the hepatopancreas and serum of grass carp,respectively.Glucose,oxypurinol,taurine,lactate,creatine,glutamate,alanine,sn-glycerol-3-phosphorylcholine,glycine,phenol,hypoxanthine,acetic acid,lysine,leucine and valine were main hepatopancreas metabolites differing in normal and excessive hepatopancreas lipid grass carp.Among the above metabolites,only glucose and oxypurinol in the excessive hepatopancreas lipid group were higher than those in the normal hepatopancreas lipid group.Lactic acid,glucose,creatine,citric acid,leucine,valine,proline,pyruvic acid,guanosine,isoleucine,glutamate,sn-3-of glycerol phosphocholine,alanine,lysine and glycine were main serum metabolites differing in normal and excessive hepatopancreas lipid grass carp.Among the above serum metabolites,only glucose,citric acid,glutamate,proline,sn-glycerol-3-choline phosphate,arginine and glycine in grass carp with excessive hepatopancreas lipid were higher than those in the normal hepatopancreas lipid group.It is concluded that both aerobic oxidation and glycolysis of glucose in the body of grass carp with excessive hepatopancreas lipid are obviously inhibited and the metabolism of amino acids are abnormal,which may be one of the important biochemical causes of excessive lipid accumulation in hepatopancreas of grass carp.