Five patients treated for intracranial cerebral hemorrhage after superficial temporal artery-middle cerebral artery bypass in Xuwu Hospital, Capital Medical University, Beijing, China, from 2005-2011 were included in this study. Prior to superficial temporal artery-middle cerebral artery bypass, all patients showed diminished cerebrovascular reactivity and an ipsilateral ischemic lesion. Intracranial cerebral hemorrhage developed within 1-4 days following superficial temporal artery-middle cerebral artery bypass. Transcranial Doppler showed increased middle cerebral artery velocity of 50-100% in the operated hemisphere. These findings suggested that focal hyperperfusion, an ipsilateral ischemic lesion and diminished cerebrovascular reactivity are the important characteristics of intracerebral hemorrhage following superficial temporal artery-middle cerebral artery bypass in patients with steno-occlusive cerebrovascular disease.