Abstract: Based on the search of conjugate gradient which has changed steps and com-pressibility factors,a new fast learning method is proposed countering the drawbacks of theslow convergent speed and the local minimun of BP method. By comparison with BP methodalgorithm, the new method has not only faster learning speed but also higher accuracy,Itshows that the exptrapolation of the new algorithm is better than that of the least squaremethod in estimation some distillation column.