Primary pulmonary tuberculosis in children is the most common type of primary tuberculosis. It is the primary infection that occurs after the tuberculosis bacteria invade the lungs for the first time. It is the main type of pulmonary tuberculosis in children, accounting for 85.3% of the total number of various types of pulmonary tuberculosis in children. Primary pulmonary tuberculosis includes primary syndrome and bronchial lymph node tuberculosis. The former is composed of primary pulmonary lesions, local lymph node lesions and lymphangitis connected to the two; the latter is mainly composed of enlarged lymph nodes in the chest cavity. The primary pulmonary lesions are either small in range or covered by mediastinal shadows, which cannot be detected by X-rays, or the primary lesions have been absorbed, leaving only local enlarged lymph nodes, so they are clinically diagnosed as bronchial lymph node tuberculosis. These two are combined into one type, namely primary pulmonary tuberculosis.