A ground glass nodule is not necessarily lung cancer. A ground glass nodule is an imaging concept that refers to imaging features in the lungs that resemble ground glass changes when a CT exam is performed during a physical examination. Minor bleeding and inflammation in the lung may show ground glass-like imaging changes. Lung cancer has a strong relationship with ground glass shadow, because all lung cancers show nodular shadow in early stage, especially atypical adenomatous hyperplasia, carcinoma in situ, or gastric infiltrating carcinoma, the imaging presentation may be ground glass nodular shadow. For people with ground glass nodules, they should not be negligent and must be carefully screened by professional doctors. If the nodules have a higher chance of being benign, a follow-up approach may be taken, and if the chance of malignancy is higher, early intervention may be performed after relevant evaluation.