Objective　To investigate the effect of plasma exchange (PE) therapy on children with atypical hemolytic uremic syndrome (aHUS) in their acute phase. Methods　The clinical data of 16 patients with aHUS treated by PE from May 2014 to May 2017 were retrospectively analyzed. Results　In 16 children (10 males and 6 females) aged from 1 to 14 years old, 16 patients received 2 to 5 times PE respectively and Prisma flex were used with Pirsma TPE1000 or TPE2000 membrane plasma separator. The amount of PE is about 40 ~ 60 mL/kg each time. After treatment, the condition in 15 children's was improved in one month except the one who gave up the treatment after four PE treatments. Conclusions　PE can rapidly relieve the condition of aHUS in children as one of the important treatment methods in acute stage.