Ground glass nodules in the lungs are not necessarily lung cancer, but it is important to rule out lung cancer in clinical practice. Ground glass nodules in the lungs can also be seen in lesions such as tuberculosis, bacterial or fungal infections, and sarcoidosis, all of which are benign lesions, while lung cancer is a malignant lesion. Whether it is lung cancer or other benign lesions depends on the imaging characteristics of the ground glass nodules, the speed of development, and the response to treatment. Generally, pneumonia will have fever, cough and yellow sputum, which are effective in anti-infection treatment, while tuberculosis infection is often multiple lamellar shadows in the lung with changes such as pleural thickening and pleural effusion, which are effective in anti-tuberculosis treatment and will be absorbed and disappear rapidly, while fungal infection is often ground glass shadow with cavity-like changes. The specific nature of the lesion can only be determined by a puncture biopsy of the pulmonary ground glass nodule or pathology after surgical excision.