Solid nodules in the lungs may be benign or malignant; benign nodules are usually not serious; malignant nodules may lead to adverse outcomes if not intervened in time. Solid nodules in the lungs may be infected foci, tuberculosis foci, pulmonary nodular disease, primary malignant tumors of the lungs, metastatic tumors, and so on. 1. Among them, pulmonary nodular disease, infected foci, and tuberculosis foci are benign nodules. Nodular disease does not require treatment if asymptomatic, and regular observation and follow-up is sufficient. Infected foci and tuberculosis need to be treated according to their conditions. 2. For malignant nodules such as primary malignant tumors and metastatic tumors in the lungs, they may grow faster or develop distant metastasis earlier, which seriously affects the survival time and quality of life of the patients, and the situation is more terrible. It is recommended to go to the hospital in time when solid nodules appear in the lungs, and according to the doctor’s suggestion, choose enhanced CT, puncture biopsy and other measures to clarify the nature of the nodules, and actively treat them.