Objective: To establish quality control method of effective fraction from Catharsius molossus Linnaeus.Method: Amino acids were identified by TLC.Molecular weight was studied by sodium dodecylsulfate-polyacrylamide gel electrophoresis（SDS-PAGE）.The type and content of amino acids were detected by automatic amino acid analyzer.Result: For thin-layer chromatography（TLC）

the spots of effective fraction from Catharsius molossus Linnaeus are clearly

and displayed similar spots with reference substances;For SDS-PAGE

the effective fraction were mixture of polypeptides

and molecular weight distributed from 6 × 103 to 14 × 103;For determination of amino acids

17 amino acids were detected except destruction of tryptophan.The content of free amino acid was 13.41%

and content of combined amino acid or peptide was about 9.27%.Conclusion: The method was sensitive

accurate

reproducible and exclusive.It can be used for quality control of effective fraction from C.molossus.