With the popularization of CT technology, more and more multiple primary lung cancer, that is, the simultaneous presence of more than one primary cancer in the lungs, has been detected. Imaging can make a rough judgment, histopathology is still the diagnostic gold standard, and molecular genetics examination can better distinguish it from intrapulmonary metastatic cancer when necessary. At present, there is no unified treatment standard for multiple primary lung cancer. Surgery is the most important and effective means, and the surgical method needs to be personalized according to the size and distribution of the patient's lesions, one-sided lobectomy and the other side sublobar resection is considered safe and feasible. At the same time, local nonsurgical treatment is also an option or a supplement to surgical treatment. This article reviews the diagnosis and treatment of multiple primary lung cancer in recent years.