Abstract: The extensive application of radiotherapy and the long survival of patients with malignant tumors have led to an increased incidence rate of radiation-induced osteosarcoma(RIOS), one of the most critical radiation-induced complications.Compared with primary osteosarcoma, RIOS has higher grade and poorer prognosis, which reduces the survival of patients with cancers.However, RIOS has not been fully understood in the clinical setting.This paper summarizes the latest progress at home and abroad, focusing on the incidence rate, risk factor, latency, and diagnostic criteria of RIOS.The molecular mechanism of RIOS is associated with the mutation of p53, the activation of the Wnt/β-catenin signaling pathway, and the superposition of multiple alleles.Furthermore, we discuss the differences in clinical characteristics, imaging findings, treatment, and prognosis between primary osteosarcoma and RIOS.