A tumor on the lung is not necessarily cancer. Lung cancer is just a common type of malignant tumor of the lung. Tumors on the lung can be classified as benign tumors and malignant tumors according to their nature. Tumors on the lung can be divided into primary and secondary tumors according to the source of the tumor. Among primary tumors of the lung, lung cancer occupies a very high chance. Lung cancer is a malignant tumor formed by alveoli and bronchial epithelial cells at all levels, and tumors of the lung include lung cancer. Lung cancer is diagnosed by chest radiography, CT and MRI of lung, and pathological examination by bronchoscopy to confirm the staging of lung cancer. The early symptoms of lung cancer are cough, blood in sputum and pain in the chest. People with chronic respiratory diseases should have regular annual chest examination to detect and treat the disease as early as possible. Secondary tumor of the lung is a malignant tumor that originated in other parts of the body and metastasized to the lung. This condition is quite common and most of them are hematogenous metastases. Common primary malignant tumors include gastrointestinal tract, genitourinary system and liver, thyroid, breast, bone, soft tissue, skin carcinomas and sarcomas. Benign tumors can be removed by surgery and most of them are cured without recurrence. Lung cancer needs to be diagnosed and treated as early as possible. The treatment method is based on the condition, mainly surgery, combined with chemotherapy, radiotherapy, targeted and immunotherapy as a comprehensive therapy.