Objective To study the therapeutic effect of plasma exchange and plasma perfusion(PE+PP)on acute fatty liver of pregnancy.Methods Twenty-one patients with acute fatty liver of pregnancy were divided into two groups.In the treated group,the patients were treated with (PE+PP) on the basis of the conventional therapy,and the control group received the conventional therapy only?Liver function,kidney function and prothrombin activity(PTA) before treatment and 4 weeks,6 weeks after treatment were observed.Results After treatment with (PE+PA),the liver function,kidney function and PTA were ameliorated at 4 weeks and 6 weeks(P