Early stage of small cell lung cancer is mainly screened by chest CT or chest X-ray, and pathologic examination to clarify the nature and staging. Small cell lung cancer is one of the lung cancer types, belonging to low differentiated neuroendocrine carcinoma, which is named because of its small cancer cells under the microscope. It is characterized by high malignancy and rapid proliferation. Early lung cancer often has no obvious clinical symptoms, and a few patients have symptoms such as irritating dry cough. It is usually detected by routine physical examination. X-ray chest radiography is the most commonly used method, which can detect more obvious lung nodules i.e. early lung cancer, but for tiny lung nodules, the resolution is lower. Chest computed tomography (CT) has a higher resolution and can detect small lesions and areas that are not easily visualized by X-ray. If lung cancer is highly suspected, further examination is needed, and pathologic examination is the gold standard for lung cancer examination. Invasive examinations such as bronchoscopy, thoracoscopy or CT-guided puncture biopsy, and immunohistochemical typing under pathoscopy confirm the diagnosis. Early stage lung cancer is mainly detected through physical examination. It is recommended to have regular physical examination every year and maintain a healthy lifestyle.