Osteochondroma is the common name for osteochondroma. The chance of malignant transformation of a single osteochondroma is generally low, less than 1% has been reported in the literature, while the chance of cancerous transformation of multiple osteochondromas is relatively high, generally less than 10%. Osteochondromas are bony elevations, developmental malformations of bone and cartilage growth. Osteochondroma is a developmental malformation of bone and cartilage growth, and there are single and multiple osteochondromas, with the majority being single, and the ratio of single to multiple osteochondromas is about (8-10):1. Osteochondroma may be malignant, and malignant osteosarcoma may become chondrosarcoma. According to the literature, the malignant rate of single osteochondroma is less than 1%, and the malignant rate of multiple hereditary osteochondromas is less than 10%. Whether osteochondroma is malignant or not is mainly based on its growth degree, if the thickness of cartilage cap of osteochondroma is more than 25mm, it should be timely performed pathological biopsy to check whether it is malignant or not. The chances of osteochondroma becoming cancerous are only medical statistics, but for the specific condition, it is necessary to consult regular hospitals and complete relevant examinations, so that the doctors can give correct judgment according to the symptoms, signs and auxiliary examinations, and guide the treatment, and the doctors should not diagnose and treat the case blindly on their own, so as to avoid the delay of the condition.