Objective To analyze MRI features and clinical presentations of progressive multifocal leukoencephalopathy(PML) in Acquired Immune Deficiency Syndrome(AIDS)patients, to deepen the understanding of the disease. Methods 8 cases of progressive multifocal leukoencephalopathy in AIDS patients were confirmed by clinic. 7 cases were performed conventional MRI, 1 case was performed conventional MRI(including DWI), enhanced MRI, and MR spectroscopy(MRS). Location of lesions, characteristics of signal on MRI, and clinical presentation were analyzed retrospectively. Cerebrospinal fluid (CSF) JC virus was tested in 8 patients. Results PML occurred supratentorial in 3 cases, occurred infratentorial in 1 case, and involved both supratentorial and infratentorial in 4 cases in our series. The lesions involved bilateral head of caudate nucleus in 1 case. Supratentorial lesions located in the highest blood flow subcortical white matter. The involvement in supratentorial and infratentorial white matter shows asymmetric and no occupying effect. The lesions appear as hyperintensity on T2-weighted and FLAIR (fluid attenuated inversion recovery) images and hypointensity on T1-weighted images. The lesions in frontal lobes showed hyperintensityin on DWI sequence, and appeared patchy hyperintensity in enhanced images. MRS was performed on the lesions in the heads of caudate nucleus. N-acetyl aspartate (NAA) peak in the lesions were decreased than that of the control, and Choline(Cho) peak and Lactate(Lac) peak were increased . Clinical presentation of PML are nonspecific. The most common symptoms presented limb weakness, hemiplegia，hemidysesthesia, and progressive cognitive dysfunction. From PML diagnosis to death time was from 3 weeks to 14 months in our series. JC virus in CSF were positive in all 8 patients. Conclusion There are typical MRI findings of PML in AIDS patients. A combination of positive JC virus-DNA test in CSF can be used to diagnose PML. The PML is a subacute, rapid-developing clinical course with a high mortality.