OBJECTIVE： To observe clinical efficacy of carboxymethyl starch in the treatment of recurrent respiratory infection （RRI） children. METHODS： 110 RRI children were selected and randomly divided into observation group and control group， with 55 children in each group. Control group was given routine treatment， such as anti-infection， anti-virus， abatement of fever， relieving cough， phlegm transformation and etc. Observation group was additionally given Carboxymethyl starch sodium solution （7 ml for ＜4 year-old， 10 ml for 4-7 year-old， 15 ml for ＞7 year-old） on the basis of control group. Both groups received consecutive treatment for 3 months. The changes of cellular immunity function index CD4+， CD8+ and CD4+/CD8+ and humoral immunity index IgG， IgA and IgM were observed in 2 groups before and after treatment， and clinical efficacy was evaluated in 2 groups. RESULTS： There was no statistical significance in CD4+， CD8+ and CD4+/CD8+ levels of control group before and after treatment （P＞0.05）； after treatment， CD4+ and CD4+/CD8+ of observation group obviously increased， while CD8+ level obviously declined； the observation group was better than control group， with statistical significance （P＜0.05）. There was no statistical significance in IgG， IgA and IgM levels of control group， with statistical significance （P＞0.05）； after treatment， IgG， IgA and IgM levels of control group increased significantly， and the observation group was better than control group， with statistical significance （P＜0.05）. Total effective rate of observation group was 92.73％， which was much higher than that in control group （78.18％）， with statistical significance （P＜0.05）.  CONCLUSIONS： Carboxymethyl starch has definite therapeutic efficacy on RRI， and can obviously improve cellular and humoral immunity function.