Objective To investigate the effect of vitamin A on immune regulation in children with recurrent respiratory tract infection(RRTI),and to provide reference for clinical treatment. Methods Infants of 0.5~3 years old from January 2015 to January 2016,353 cases of RRTI in were divided into treatment group (176 cases) and control group (177 cases).Two groups were given routine treatment of anti infection and symptomatic treatment,treatment group based on the use of oral vitamin A (20 thousand U/D),after 3 months of follow-up,T cell subsets and immunoglobulin were detected before and after treatment,and two groups of clinical curative effect evaluation,recurrence times during follow-up of patients with RRTI. Results T immune globulin treatment group (IgG,IgA,IgM),cell subsets (CD₃,CD₄,CD₄/CD₈) were significantly higher than that before treatment,the difference was statistically significant (P<0.05);The control group before and after treatment with immunoglobulin and T cell subsets had no significant difference;Treatment after the comparison of the results between groups,the treatment group of immunoglobulin (IgG,IgA,IgM) were higher than the control group (P<0.05),especially T cell subsets (CD₃,CD₄,CD₄/CD₈) with significant statistical differences.During the period of 3 months,the average number of respiratory infections among the two groups was compared.The results showed that the treatment group was significantly less than the control group (P<0.05). Conclusion Vitamin A can improve the immunity of infants and young children with RRTI,and reduce the frequency of recurrence of the disease and shorten the course of disease,it is worthy of clinical application.