Objective To understand the epidemiological characteristics of child pneumonia mycoplasma infection to provide a forceful basis for its clinical diagnosis and treatment.Methods A total of 6 823 children outpatients and inpatients with pneumonia in this hospital from January 2015 to December 2016 were performed the serum Mycoplasma pneumoniae antibody detection by using the passive agglutination method.Results (1) Among 6 823 children cases,Mycoplasma pneumonia antibody positive detection was in 1 843 cases,the positive rate was 27,01 ％,among them,the infection rate of female was higher than that of male (32.68％ vs.23.21％,P＜0.01).(2) Mycoplasma pneumoniae antibody detection rates in ＜1 year old,1-＜3 years old,3-＜6 years old,6-14 years old were 5.41％,28.01％,40.34％ and 43.81％ respectively (P＜0.01),the total detection rate in ≥ 3 years old group was higher than that in ＜3 years old group (P＜0.01).Conclusion Mycoplasma pneumoniae infection rate is higher among children with respiratory tract infection,the incidence rate in school-age children is lower.The autumnand winter seasons are prevalent.