OBJECTIVE To study the clinical value of C-reactie protein(CRP)detection in diagnosis of the pediatric bacterial pneumonia and the Mycoplasma pneumonia so as to guide the diagnosis of infantile pneumonia.METHODS The children with bacterial pneumonia(the bacterial pneumonia group)and the children with Mycoplasmapneumonia(the Mycoplasmapneumonia group),who were treated in the pediatrics department from Sep 2010to Sep 2012,were enrolled in the study,the healthy children receiving the medical examination(the control group)were also selected,with 80cases in each group,then the change of CRP level was determined.RESULTS The CRP level of the control group was(3.24±0.45)mg/L,the bacterial pneumonia group before treatment(44.03±5.83)mg/L,the bacterial pneumonia group 3days after the treatment(15.12±6.21)mg/L,the Mycoplasma pneumonia group before treatment(13.97±4.96)mg/L,the Mycoplasma pneumonia group 3 days after the treatment(5.29±2.33)mg/L,the CRP level of the bacterial pneumonia group and the Mycoplasma pneumonia group before the treatment was significantly higher than that of the control group(P0.05),the CRP level of the bacterial pneumonia group was higher than that of the Mycoplasmapneumonia group(P0.05),the CRP level of the bacterial pneumonia group 3days after treatment was higher than that of the Mycoplasma pneumonia group(P0.05),the difference in the CRP level before and after the treatment between the bacterial pneumonia group and the Mycoplasma pneumonia group was statistically significant(P0.05).The positive rates of the CRP of the bacterial pneumonia group were 100.00% before the treatment and 52.50% 3days after the treatment,which were respectively 66.25%and 21.25%in the Mycoplasmapneumonia group,the difference in the positive rate before and after the treatment between the bacterial pneumonia group and the Mycoplasma pneumonia group was statistically significant(P0.05).CONCLUSIONThe positive rate of CRP is the highest in children with bacterial pneumonia,and the detection of CRP is conducive to distinguishing between the bacterial pneumonia and the Mycoplasma pneumonia.