Pure ground glass nodules are not necessarily cancerous, but lung cancer should be ruled out. Pure ground glass nodules can be tuberculosis infection, fungal infection or common bacterial infection, and the exact nature of the lesion has to be determined by combining imaging, clinical manifestations and response to treatment, mainly by pathological puncture biopsy or surgical confirmation of ground glass nodules. If it is accompanied by fever, cough and yellow sputum, and dissipates and absorbs significantly after anti-infection treatment, it is most likely a bacterial infection of the lung, while if it can dissipate and absorb through anti-tuberculosis treatment or antifungal treatment, it is often a tuberculosis infection or fungal infection. Therefore, purely ground glass nodules may not necessarily be lung cancer, but the possibility of lung cancer should be excluded.