The causative agent of Mycoplasma pneumoniae pneumonia is Mycoplasma pneumoniae, which is the smallest microorganism that grows non-intracellularly and has no cell wall. The disease accounts for about 20% of pediatric pneumonia and up to 50% in dense populations. It can occur year-round and is mainly transmitted through the respiratory tract. Infection with Mycoplasma pneumoniae can lead to multisystem immune damage. The disease is not only seen in older children, but also in infants and children with infection rates as high as 25-69%. The clinical picture is often feverish, with a variable fever pattern and a fever duration of 1-3 weeks. Irritating cough is the prominent manifestation, and some of them resemble whooping cough and may cough up sticky sputum or even blood. Older children may complain of sore throat, chest tightness, chest pain and other symptoms, but pulmonary signs are often not obvious. In infants and young children, the onset of the disease is rapid, the duration of the disease is long, and the disease is severe, with dyspnea, wheezing and rales in both lungs being more prominent, and wet rales can be heard. Some children have multisystem involvement, such as myocarditis, pericarditis, thrombocytopenia, meningitis, hepatitis, hepatosplenomegaly, and various skin rashes. The disease may start directly with extrapulmonary manifestations or may be accompanied by symptoms of respiratory tract infection. It is believed that children with fever and cough, along with involvement of other organs and increased blood sedimentation, but not severe toxic symptoms, should consider Mycoplasma pneumoniae infection and must undergo further appropriate laboratory tests. X-ray changes are divided into 4 types: 1. predominantly increased weight of hilar shadow; 2. bronchopneumonia; 3. interstitial pneumonia; 4. homogeneous solid lung changes. Inconsistent with clinical manifestations, heavy cough with mild pulmonary signs; mild signs but significant chest radiograph shadows. Detection of mycoplasma IgM antibodies in the serum has diagnostic significance. Treatment of Mycoplasma pneumoniae infection is mainly the macrolide erythromycin or azithromycin. The course of treatment can be as short as 1-2 weeks or as long as 3-4 weeks, or even longer. Because Mycoplasma pneumoniae antibody testing is limited by the duration of infection, it is essential to empirically select macrolides for treatment of suspected recent infection before test results are obtained. Treatment with effective antibiotics can shorten the course of the disease, reduce symptoms, and decrease the occurrence of complications. If treatment is incomplete and the pathogen is not completely cleared, the disease is prone to recurrence, and even Mycoplasma pneumoniae may be isolated from the respiratory secretions of the child for several months, thus becoming a transmitter of the infection.