Objective To investigate the imaging features and diagnostic value of CT and MRI in femoral osteosarcoma. Methods A total of 17 patients with femoral osteosarcoma in our hospital from November 2014 to October 2017 were selected for pathological examination, CT and MRI examination. The diagnostic accuracy of CT and MRI for femoral osteosarcoma and related features of femoral osteosarcoma (Codman triangle, soft tissue mass, periosteal reaction, tumor bone and bone destruction) was compared statistically. The pathological features, CT and MRI findings of the patients were analyzed. Results The diagnostic accuracy of MRI for femoral osteosarcoma (94.12%) was higher than that of CT (82.35%), but the there was no statistically difference(P＞0.05). The diagnostic accuracy of MRI for Codman triangle (41.18%) was lower than that of CT (64.71%), but there was insignificant difference between them(P＞0.05). The diagnostic accuracy of MRI for soft tissue mass, periosteal reaction and bone destruction (94.12%, 88.24%, 100%) was higher than that of CT(P＜0.05). The diagnostic accuracy of MRI for bone tumors (58.82%) was lower than that of CT(P＜0.05). Conclusion CT and MRI can be used for diagnosis of femoral osteosarcoma and its related signs, which has significant advantages in the early diagnosis and the determination of the scope of invasion. It can provide certain reference for the early clinical development of targeted intervention programs.