Abstract: Objective: To investigate the serum levels of interleukin-17(IL-17) and transforming growth factor-β1(TGF-β1) in children with chronic persistent asthma,and its clinical significance.Methods: Ninety children with chronic asthma were divided into the mild group(56 cases) and moderate severe group(34 cases) according to the disease condition,and 30 healthy children were set as the control group.The FEV1% and serum levels of IL-17 and TGF-β1 in 3 groups were detected by pulmonary function test and ELISA,respectively.Results: The serum levels of IL-17 in the mild group and moderate severe group were(103.44±7.20)pg/mL and(147.31±4.42)pg/mL,which was significantly higher than that in control group(67.43 ±3.49)pg/mL(P<0.01).The serum levels of TGF-β1 in mild group and moderate severe group were(55.58±8.46)pg/mL and(80.26±4.62)pg/mL,which was significantly higher than that in control group(32.61±6.45) pg/mL(P<0.01).The serum levels of IL-17 and TGF-β1 were negatively correlated with FEV1%(P<0.01),and the level of IL-17 was positively correlated with TGF-β1(P<0.01).Conclusions: The chronic persistent asthma can lead to the changes of the IL-17 and TGF-β1 levels,which is closely related to the disease condition,and the TGF-β1 and IL-17 involve in the pathogenesis of bronchial asthma.