Objective To explore the clinical efficacy of Montelukast sodium in the treatment of postinfectious cough. Methods 110 cases of patients with postinfectious cough that met the inclusion criteria were divided randomly into two groups. In the treatment group, 58 cases of patients were given Mon-telukast sodium 10mg once daily, 5 days for a course of treatment. In the control group, 52 cases of patients were given Aminophyl ine Tablets, three times a day, each time 0.1 g, 5 days for a course of treatment. Results Effective rate of treatment group was 96.55%, effective rate of control group was 82.69%. The difference was statistical y significant(P<0.05). Conclusion Treating postinfectious cough with Montelukast sodium is effective, which should be widely used.