Abstract: OBJECTIVE To evaluate the clinical significance of licorzinc in the treatment of mycoplasma pneumonia(MPP) in children aged 3-6 and its possible mechanism. METHODS Sixty-two patients with MPP were randomly divided into 2 groups, 30 patients in control group were treated with azithromycin and symptomatic treatment; 32 patients in treatment group were treated with licorzinc besides conventional therapy. Then the clinical indexes, cell immunity and humoral immunity before and after treatment were observed. RESULTS The clinical effects in the two groups were equivalent(P>0.05). Recurrent respiratory tract infection significantly reduced in treatment group after six months follow-up(Ρ<0.05). IgA increased and complement C3 and C4 decreased in two groups after treatment, while CD8 increased in control group after treatment(Ρ<0.05). The level of complement C4 and CD8 were lower and CD4 was higher in treatment group compared after treatment (Ρ<0.05). CONCLUSION Licorzinc helps to reduce recurrent respiratory tract infection and restore the body's immune balance, and no adverse reaction is observed.