By using multivariate discriminant analysis of 4 morphological characteristics(total-length, body-length, body-high, body-weight), the morphological discriminant function for the identification of Carossius aurattis curieri T, et S. and Carasstus auratus auratus (L.) is yielded. Instead of general taxonomic method, this mathematical method is simple and easy to be applied in fishery practice. The function has been tested as of high significance, with 100% correct rate.A brief introduction to the use of multivariate discriminant analysis in biology is also presented.