Bronchial asthma is a chronic airway allergy disease involving the imbalance of Th1/Th2. Th2 shift is one of the primary causes of asthma. Recent studies have found that T cell immunoglobulin and mucin domain molecule 1 (TIM-1) play important roles in T cell activation and Th1/Th2 differentiation in asthma, which has been intensively reported in recent researches. This article reviews the characteristics of TIM-1 gene and its role in the pathogenesis of bronchial asthma.