Pulmonary nodules of 3mm are microscopic nodules and do not require surgical removal for treatment, but require dynamic follow-up and observation of changes in the nodules. Lung nodules are classified into 3 types: ground glass nodules, partially solid nodules and solid nodules. Nodules smaller than 5 mm are mostly benign nodules with no clinical symptoms and are chronic inflammatory changes, which do not require special treatment. Therefore, benign nodules of 3 mm in the lung are not accompanied by clinical symptoms, and if the patient has no long-term smoking history and has not had tuberculosis in the past, there is even less need to be overly nervous. Because 90% of microscopic nodules are mostly benign nodules, no specific treatment is needed, as long as the nodules are dynamically followed up with high-resolution CT of the chest to see if they show growth changes. People who usually smoke are advised to quit smoking to avoid stimulating repeated nodule growth.