UNLABELLED: Stroke is the second leading cause of death worldwide. Acute ischemic stroke (AIS) patients often exhibit hypercoagulable state and gut microbiota dysbiosis. However, the association between coagulation abnormalities and gut microbiota dysbiosis in AIS patients and their predictive value for poor functional outcomes in AIS has not been investigated. Our study enrolled 95 AIS patients and 81 healthy controls, using 16S rRNA sequencing to analyze gut microbiota composition. Baseline fibrinogen level was found to be an independent risk factor for poor functional outcomes at 90-day follow-up (odds ratio = 2.16, 95% confidence interval: 1.02-4.59, IMPORTANCE: Acute ischemic stroke (AIS) patients often exhibit hypercoagulable state and gut microbiota dysbiosis. However, the relationship between hypercoagulable state and gut microbiota dysbiosis in AIS patients and their predictive value for poor functional outcomes has not been fully explored. Our study of 95 AIS patients showed that baseline fibrinogen level was an independent risk factor for poor functional outcome at 90-day follow-up in AIS patients. Hypercoagulable state in AIS patients correlates with gut microbiota dysbiosis. AIS patients with hypercoagulable state had increased