Objective To study the changes in number and function of peripheral blood T helper cell 17(Th17) in acute urticaria patients .Methods The percentages of Th17 in peripheral blood from 50 acute urticaria patients and 50 healthy persons were ana‐lyzed by immunofluorescence staining and bicolor flow cytometry (FCM ) in vitro .Retinoic acid‐related orphan nuclear receptor γt (RORγt) mRNA from the same research objects were detected by quantitative realtime PCR (qPCR) method .Peripheral blood transforming growth factor‐β(TGF‐β) ,interleukin(IL)‐6 ,IL‐17A and IL‐17F were tested by enzyme linked immunosorbent assay (ELISA) from the same research objects .Results The quantity of percentages of Th17(t= 36 .634 1 ,P< 0 .05) and levels of RORγt mRNA(t=23 .840 1 ,P<0 .05) in urticaria patients were higher than those in healthy persons obviously .Meanwhile ,the levels of TGF‐β(t=15 .521 1 ,P<0 .05) ,IL‐6(t=7 .247 3 ,P<0 .05) ,IL‐17A(t=15 .415 3 ,P<0 .05) and IL‐17F(t=13 .032 1 , P<0 .05) in urticaria patients were higher than those in healthy persons significantly .Conclusion Dysfunction of Th17 in periph‐eral blood may involve in the immunopathogenesis of acute urticaria .