Obstructive sleep apnea(OSA) is an important but frequently ignored risk factor of ischemic stroke. The devastating disability after stroke result in socioeconomical burden and warrant better preventing strategy. The talk will focus on the epidemiology of OSA and ischemic stroke and discuss about the bidirectional mechanisms of OSA and stroke. We will also provide current evidence of treatment of OSA benefits ischemic stroke prevention. Besides, we will point out the future direction of clinical studies of OSA in stroke patients. In the end, we will share our experience of treating OSA in stroke through a clinical case.