We did a review of the clinicopathological data and treatment of one case who was successively found with small intestine cancer,hairy cell leukemia and primary lung cancer from 2010 to 2016. The multiple primary cancers are easily misdiagnosed as the metastasis and complications of the first tumor,thus,the origin and characteristics of the tumor should be determined based on the status of tumor cell morphology,histological features and molecular pathological features. Furthermore,multidisciplinary collabor...