Objective To investigate the imaging features of alveolar sort part sarcoma (ASPS), in order to further improve the understanding of the disease. Methods 5 cases with pathologically (surgery or biopsy) proved ASPS were analyzed retrospectively. Imaging features, including lesion edge, the deep fascia integrity, density/signal, tumor blood vessels in/around the masses and strengthening characteristic, were observed respectively. Results 4 cases were characterized by irregular edge and deep fascia invaded. 3 cases happened in the lower extremities, 1 case happened in pelvis.1 case happened in right kidney also had an irregular edge. CT was performed in 1 case, which showed low, mixed slightly higher density on plain scan. On MRI images of 4 cases, the masses showed hyper intensity on T1-weighted images and high intensity on T2-weighted images. And there were point-strip flow void signal in and around the masses. The masses showed heterogeneous(1 case) or homogeneous( 3 cases) enhancement after contrast. Tumor blood vessels could be seen in and around the masses. 5 cases were underwent surgery treatment, with metastases of 3 cases, 1 case metastasized at presentation, and lung or liver metastases were found after resections in other 2 cases. Conclusion ASPS has certain characteristics, which is slightly high density on CT plain scan, a bit higher/high signal on T1WI, flow void signal in and around the masses and the deep fascia integrity. But the final diagnosis still depends on histopathological examination.