The study aimed to detect the expression of the Th1-specific cell surface protein T cell Ig and mucin domain-containing molecule-3 (Tim-3) mRNA in peripheral blood lymphocytes isolated from asthmatic patients and to examine the correlation among Tim-3 mRNA, interleukin-4 (IL-4), interferon-γ (IFN-γ) level, and FEV1/FVC (force expiratory volume in one second/forced vital capacity) to explore the role of Tim-3 in the development and progression of asthmatic inflammation. Tim-3 mRNA expression was detected by reverse transcription polymerase chain reaction (RT-PCR). The IL-4 and IFN-γ levels were determined by using enzyme-linked immunosorbent assay (ELISA). The correlation among Tim-3 mRNA, IL-4, IFN-γ level, and pulmonary ventilatory capacity was analyzed. The expression of Tim-3 mRNA in patients with acute asthma exacerbation was 0.39±0.06, significantly higher than that in patients at the remission stage and controls (0.18±0.05 and 0.07±0.03, <0.05). The level of IL-4 in patients with acute asthma exacerbation was 68.42±10.54, significantly higher than that in the patients at the remission stage and controls (41.83±9.37 and 32.75±8.16, <0.05). The level of IL-4 in patients in remission was significantly higher than that in controls ( <0.05). The level of IFN-γ in patients with acute asthma exacerbation was 65.74±7.85, significantly lower than that in patients in remission and the control group (120.84±11.62 and 139.65±13.47, <0.05). The level of IFN-γ in patients in asthma remission was significantly lower than that in controls ( <0.05). Tim-3 mRNA expression was positively correlated with the level of IL-4 ( =0.68, <0.05) and negatively with the level of IFN-γ and pulmonary ventilatory capacity ( =-0.85, =-0.76, both <0.01). The increased expression of Tim-3 mRNA in peripheral blood lymphocytes might be involved in the development and progression of asthmatic inflammation.