Whether multiple ground glass nodules in both lungs with a diameter of 0.2 to 0.8 cm is serious needs to be analyzed based on the nature of the lung nodules. Multiple ground glass nodules in both lungs are density shadows found in patients undergoing chest CT. Multiple ground-glass nodules in both lungs with a diameter of 0.2-0.8 cm usually need to be observed. If the nodules decrease in size during the observation period, they are considered to be benign lesions, which are not serious at this time and need to be followed up on a regular basis. If the nodule increases in size, it is more serious and surgery or biopsy should be considered. Multiple ground-glass nodules in both lungs may be benign, such as tuberculosis or silicosis, or malignant, such as early-stage adenocarcinoma or metastatic tumor. Therefore, patients with multiple ground-glass nodules in both lungs should seek prompt medical attention and regular follow-ups under the guidance of a doctor to avoid adverse effects.