Osteochondroma is a clinically common benign bone tumor that occurs mostly in children or adolescents, and is rarely seen in adult finger bones. There are two common theories of tumor occurrence: 1. The theory of epiphyseal plate cell separation, proposed by Virchow: epiphyseal plate chondrocytes are separated from the epiphyseal plate and rotated 90 degrees, and grow in the direction perpendicular to the long axis of the bone. 2. The theory of defective development of the epiphyseal plate, which is a tumor shaped by the proliferation and ossification of nests of chondrocytes originating from the periosteum, was confirmed by D. Ambrosia and Ferguson through experiments. This is a rare case of adult exostosis of the finger bone. Whether the bone tumor was caused by traumatic injury to the periosteum and long-term stimulation of the foreign body should be further investigated. Based on the radiological and general observation, osteochondroma can be divided into two types: tipped type and broad basal type, among which tipped type is common. The malignancy rate of solitary isolated osteochondroma is low, about 1%, and most of them become chondrosarcoma, and very few become osteosarcoma. In general, those with a wider base are more likely to become malignant. Osteochondrosarcoma has typical imaging features, and X-ray examination can basically make a clear diagnosis. For osteochondroma located in the epiphysis of long bones, if there is no functional effect, it is usually not treated surgically. When the tumor is large enough to compress the surrounding tissues, it should be treated surgically if it affects the function or is suspected to have malignant tendency.