[en] Hemangiopericytoma(HP) exhibits its pathologic findings different from those of meningioma or other angiomatous tumor; and its clinical behavior is unique and prognosis worse than other cases. We reviewed the CT, MR and angiographic findings of HPs and evaluated differential radiologic points of comparison between typical meningiomas and meningeal HPs. MR(n=16), CT(n=5) and angiographic imaging(n=10) were performed in 18 patients(M:F = 12:6, mean age: 45 years) with histologically proven primary HPs. We evaluated the imaging findings of HPs with respect to site, shape, size, signal intensity, enhancement characteristics, vascular signal voids, calcification, bony and adjacent sinus involvement, and angiographic findings. HPs were meningeal in 14 cases and nonmeningeal in four. Meningeal HPs were located in the parasagittal region(n=8), convexity(n=3), intradural extramedullary space(n=1), choroid plexus(n=1), and olfactory groove(n=1). Nonmeningeal HPs were located in the masticator space(n=2), paraspinal area(n=1) and supraclavicular area(n=1). The mean maximal dimension of tumors was about 5.4cm and their shape was papillary(n=8) or lobulated(n=7). MR images showed high(n=13) or iso(n=3) signal intensities on T2W1, and heterogeneity on T2W1(n=9). Vascular signal voids in the mass were seen in all cases, while in two cases, CT scanning showed nodular dense calcification. Bone destruction was present in six cases, but no hyperostosis was found. In five cases, the superior sagittal sinus was involved. Angiographic images revealed highly vascular masses supplied by the internal carotid artery(n=5), external carotid artery(n=8), descending scapular artery(n=1) and radiculomedullary artery(n=1), with delayed tumor blush during the capillary and venous phase in which there was no arteriovenous shunt. HP is one of the extra-axial tumors in which there is hypervascularity, aggressive bony destruction arising in the meningeal and extrameningeal area, and heterogeneous high signal intensity, as seen on T2W1. Calcification is rare