Circadian rhythm is a series of biological processes that oscillate within about 24 hours and are regulated by clock genes， whose synchronization is critical to the physiological homeostasis of molecular， cellular， organ systems and the whole organism. Acute ischemic stroke shows a temporal trend of circadian rhythm. Related studies suggest that circadian rhythm disturbance may be an important risk factor for acute ischemic stroke， and intervention for acute ischemic stroke may have a time-dependent effect. This review discusses the mechanisms of circadian rhythm involvement in acute ischemic stroke and outlines future research directions