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The six cases of Ewing sarcoma/peripheral primitive neuroectodermal tumor (ES/pPNET), arising intracranially in the leptomeninges, were described in the current study.Patients in this case series are with median age of 20 years and equal sex distribution.MRI examination shows the dura-based nodule, with clearly demarcated margin showing hyper/hypo-intensity signals, as well as the intense contrast enhancement within the tumor.Tumor is composed of the sheets of close packed uniform small round cells, with scanty cytoplasm, or larger tumor cells with vesicular nuclei and small nucleoli are present.The characteristic membranous expression of CD99 and the positive nuclear staining of FLI1 in tumor cells, combined with a panel of other markers, help to establish the diagnosis of primary meningeal ES/pPNET.The combined evaluation on clinical information, radiological image, histopathological findings and immunophenotypical expression of CD99 and FLI1, as well as several other markers; may play important role in the diagnosis on ES/pPNET in surgical pathology practice.Keywords: Ewing sarcoma, PNET, meninges, immunohistochemistry.