A lung ground glass nodule that has been unchanged for three years does not need to be treated, but it still needs to be followed up regularly. Three years of follow-up without change in a pulmonary ground-glass nodule does not confirm that it is necessarily benign. If the nodule is a malignant lung tumor, it may remain unchanged for a long period of time. Therefore, follow-up is still needed to evaluate the patient’s age, gender, smoking history, tumor history, family history, and the size, nature, internal echogenicity, and signs of malignancy of the nodule. A solid nodule followed up for three years without change can be confirmed as a benign tumor. Moreover, if solid nodules are malignant tumors, the growth is more active. Solid nodules with a diameter greater than 1.5 cm and ground-glass nodules with a diameter greater than 8 mm can be considered as high-risk nodules, which need to be followed up on a regular basis. During the follow-up of ground-glass nodules, the appearance of a solid component must be noted with great attention, and it is recommended to consult the respiratory medicine department of a regular hospital.