Abstract: Objective Human coagulation factor Ⅸ （hFⅨ） plays a very important role in the human endogenous coagulation. Absolute or relative lack of hFⅨ can lead to hemophilia B. In our study,Pichia pastoris was used to produce recombinanted high activity mutant hFⅨ-V107A-R338A. Methods First,PPICZaA-hFⅨ-V107A-R338A yeast expression vector was be constructed,and then transformed into Pichia pastoris SMD1168.The resistance ability recombinant strain was screened by G418,and the expression product was obtained and purified. Results The recombinant SMD1168-hFⅨ-R338A production was obtained at 80-120 mg/L in this study,which was about（44.06±2.3）% of the natural hFⅨ coagulation activity,7.75 times higher than that of the wild-type yeast recombinant hFⅨ and better than hFⅨ R338Aby 13.17）.Conclusions High activity mutant hFⅨV107A -R338A producted by Pichia pastoris might be the succedaneum of natural hFⅨ

Key words: Human coagulation factor Ⅸ, high activity mutant, Pichia pastoris, Protein expression