Abstract: Objective To explorea new convenient and rapid method to make mice models infected with cryptosporidium parvum.Methods Kunming mice were divided into 5 groups.Group 1:mice were challenged with drinking water with dexamethasone(11.25 mg/ml)and glucose(50 g/L)in it.Group 2:mice were injected with dexamethasone(0.25 mg/week per mouse)subcutaneously.Group 3:mice were injected with cyclophosphamide(2 mg/week per mouse)subcutaneously.Group 4:mice were treated with the methods of both group 1 and 2.Group 5:mice were treated with the methods of both group 1 and 3.The experiment lasted for 4 weeks.Collect the feces or intest in contents,centrifugate and then smear.Observe the emergence time and shape of C.par vumoocyst under LM with modificed acid-fast staining.Results Oocysts appeared in feces of the mice in groups 1,4 and 5 from the 5th day and existed until all mice died.But oocysts didn't appear until the end of the experiment in groups 2 and 3.The difference of survival time between groups 1 and 4 was not significant(P>0.05).The survival time of mice in group 5 was shorter than that of groups 1 and 4(P<0.05).Conclusion The test indicates that mice could be infected with cryptospor idium parvum after about 5 days by adding dexamethasone and glucose into their drinking water.