Objective To investigate the modulating roles of Clara cell secretory 16 kD protein ( CC-16) , transcription factor T-bet, and GATA-3 in airway inflammation of patients with asthma. Methods 25 patients with acute exacerbation of asthma were enrolled as an asthma group and 33 healthy volunteers were enrolled as control. The plasma levels of CC16, IFN-γ, and IL-4 were measured by enzyme-linked immunosorbent assay ( ELISA) . The mRNA expressions of T-bet and GATA-3 in the peripheral bloodmononuclear cells ( PBMCs) were measured by reverse transcription-polymerase chain reaction ( RT-PCR) .Results The levels of CC16 and IFN-γin the asthma group were lower than those in the control group [ ( 21. 96 ±7. 31 ) ng/mL vs. ( 64. 88 ±25. 27) ng/mL, ( 118. 73 ±22. 59) pg/mL vs. ( 145. 53 ±29. 50) pg/mL, both P lt;0. 01] . The IL-4 level in the asthma group was significantly higher than that in the control group [ ( 425. 22 ±4. 37) pg/mL vs. ( 69. 72 ±10. 15 ) pg/mL, P lt; 0. 01] . The T-bet mRNA expression and T-bet /GATA-3 ratio of PBMCs in the asthma group were significantly lower than those in the control group( both P lt; 0. 01) . The expression GATA-3 mRNA was significantly higher than that in the control group( P lt;0. 01) . The level of CC16 was positively correlated with T-bet mRNA expression and the ratio of T-bet /GATA-3 ( r =0. 792, 0. 761, respectively, P lt; 0. 01) . There was no correlation between CC16 and the GATA-3 mRNA expression ( P gt;0. 05) . Conclusions These results suggest that CC16 and T-bet play important protection roles in the pathogenesis of asthma. GATA-3, IFN-γ, and IL-4 also participate in the airway inflammation of asthma.