Abstract: Objective To investigate the clinical efficacy of bacterial lysates in treatment of children with recurrent lower respiratory tract infection. Methods A total of 140 children with recurrent lower respiratory tract infection were randomly divided into two groups, with 70 cases in each group. Control group was treated with routine treatment, while study group was treated with bacterial lysates based on routine treatment. The clinical efficacy, the number of recurrent respiratory infection and immune function indexes were compared between two groups. Results The total effective rate of the study group was 94.29%, which was significantly higher than 82.86% of the control group(P<0.05). The number of recurrent respiratory tract infection at 3, 6, 12 months after treatment in the study group was significantly less than those in the control group(P<0.05). After 3 months of treatment, the levels of immunoglobulin G(IgG)and immunoglobulin A(IgA)in the study group were significantly higher than treatment before and those in the control group(P<0.05), but there was no significant difference in level of immunoglobulin M(IgM)between the two groups(P>0.05). Conclusion Bacterial lysates shows a significant effect in treatment of children with recurrent lower respiratory tract infection, which can effectively enhance the immune function of children, and reduce the frequency of recurrent respiratory tract infection.