Objective To analyze the MRI findings of alveolar soft sarcoma of the extremities.Methods The clinical data and MRI findings of 10 patients with alveolar soft tissue sarcoma of the extremities were analyzed. Results There were 9 cases in deep muscle group and 1 case in superficial muscle group. 6 cases were lobulated and 4 cases were smooth. T1WI shown equal or slightly higher signal and T2WI shown uneven high signal. Tumor parenchyma was moderately or markedly enhanced and delay strengthening of circuitous vessels image after enhancement scanning. Conclusion MRI findings is the good method for the accurate diagnosis of solft tissue tumors and for valuable for pathological subtypes.