Objective:To explore the effects of voriconazole on the proliferation and morphology of Acanthamoeba cultivated in vitro,and to clarify the killing effects of voriconazole against the trophozoites and cysts of Acanthamoeba.Methods:The Acanthamoeba polyphaga at logarithmic phase were selected and divided into control group and experiment groups(2.5 and 25.0 mg·L-1).The Acanthamoeba in each group was collected at 24,48,72,and 96 h after drug administration,respectively.Then the concentrations of Acanthamoeba were calculated and the proliferation curves were drawn;inverted microscope was used to observe the morphology,activity and adherence of Acanthamoeba;the ultrastructures of Acanthamoeba were observed under electron microscope.Results:Compared with control group,the numbers of Acanthamoeba polyphaga in experiment groups were significantly decreased(P<0.01).The morphology of Acanthamoeba changed significantly under inverted microscope,and the shape of Acanthamoeba transformed from the trophozoites with irregular spiny filopodia to circular cysts.Even a large number of cell debris was observed.Different degrees of damage and even necrosis of Acanthamoeba in experiment groups were found under electron micro scope.Conclusion:Certain concentration of voriconazole can effectively inhibit the proliferation of Acanthamoeba and change the morphology and ultrastructure and kill the trophozoites and cysts of Acanthamoeba cultivated in vitro.