Lung cancer patients need an oxygen concentrator if they have difficulty breathing. Under normal condition of respiratory system, the use of oxygen concentrator is generally not necessary. Oxygen concentrator is mainly used to assist breathing for patients who are unable to breathe oxygen normally, if lung cancer patients have difficulty in breathing. Lung cancer patients need extra oxygen due to tumor progression, which affects lung function. In addition, obstructive pneumonia, pulmonary atelectasis caused by tumor, or even accompanied by large amount of pleural effusion, will also have breathing difficulties, and oxygen therapy needs to be given at this time. It should be noted that if abnormal breathing occurs in lung cancer, patients should go to the hospital in time to improve the examination, such as chest CT, sputum culture, etc., to clarify the cause of the disease and receive corresponding treatment. In daily life, patients should take active anti-cancer treatment, take medication regularly as prescribed by doctors, keep optimistic mindset, and give feedback to doctors in time if they have any discomfort.