Lung nodules are treated differently according to the size of the nodule. When the diameter of small lung nodules ≤ 8mm, observation and follow-up are considered, and small lung nodules with a diameter of >8mm can be considered for treatment or further examination to clarify the nature of the nodule. Nodules with a diameter of ≤8mm are less likely to be malignant, and the lesions are difficult to biopsy in small foci, and PET-CT and other image features that can be obtained are fewer, and CT follow-up monitoring is the most appropriate choice. CT review is usually performed at 3, 6, 12, and 24 months, and annual follow-up is available for those without changes. Further examination can be taken to clarify the nature of the nodule before proceeding to the next step of treatment if the nodule continues to increase in size during follow-up. Nodules with a diameter of >8mm should undergo CT review at 3 months, and empirical antimicrobial therapy may be considered appropriately. If the nodule does not dissipate, PET-CT, non-surgical biopsy and/or surgical resection are recommended for evaluation. Patients with no malignant tendency will continue to be observed and followed up, while those with malignant tendency or already malignant will be treated with timely surgery. Patients with small nodules in the lungs should go to the hospital in time when the nodules increase in size or change in the course of follow-up, accompanied by symptoms such as coughing, sputum, weight loss, etc., to improve the examination, to further clarify the nature of the nodules, and to take appropriate treatment under the guidance of the doctor.