Objective To explore the risk factors for the formation of airway mucus plug in children with mycoplasma pneumonia (MPP). Methods From Sep. 2011 to Apr. 2013, a total of 236 MPP children who accepted treatments in our hospital were taken as the clinical research objects, and they were divided into mucus plug group(132 cases) and control group(104 cases). The clinical data and biochemical indexes of the two groups were compared, and the risk factors for the formation of airway mucus plug in children with MPP were analyzed by Logistic regression analysis. Results In 9 possible factors (gender, age, duration of fever, pleural effusion, white blood cell count, neutrophil, C-reactive protein, lactate dehydrogenase level and first bronchofibroscope examination time), age, duration of fever, pleural effusion, C-reactive protein and lactate dehydrogenase level were associated with the formation of airway mucus plug in children with MPP. Conclusion Age, duration of fever, pleural effusion, C-reactive protein and lactate dehydrogenase level are risk factors for the formation of airway mucus plug in children with MPP, and the positive control of risk factors may contribute to the reduction of airway stenosis and obstruction.