Lung nodules that grow quickly are not necessarily malignant. Lung nodules can be divided into two categories: benign and malignant according to the type of disease. Lung nodules need to be highly vigilant if they grow fast, and detailed and formal examination should be conducted to confirm the condition. 1. Benign: benign nodules are usually caused by infection, no lobulation, sharp edges or fibrous streaks, less edge burrs, rarely see lobulation, and so on. It can be treated conservatively, and chest CT should be repeated every 3~6 months to observe the condition of the nodule. 2. Malignant: Most of the malignant nodules will have very obvious burrs on the edge, with lobulation. Generally, malignant lung nodules can be surgically resected with the doctor, or treated with chemotherapy or targeted drugs. It is recommended that the patient should consult a doctor in time, and then make appropriate treatment under the doctor’s guidance after clarifying the pathology of the lung nodule.