Nearly half of Acute Ischemic Stroke (AIS) patients failed to achieve favorable outcomes despite successful reperfusion treatment. This phenomenon is referred to as Futile Recanalization (FR). Screening patients at risk of FR is vital for stroke management. Previous studies reported the diagnostic value of alkaline phosphatase (ALP) levels in certain aspects of stroke prognosis. However, the association between serum ALP level and FR among AIS patients treated with thrombectomy remained unclear.We screened stroke patients who underwent thrombectomy at our center from January 2017 to June 2021, and those who achieved successful reperfusion (modified Thrombolysis in Cerebral Infarction score=3) were ultimately analyzed. Demographic information, vascular risk factors, and laboratory test results were collected at admission. The 3-month unfavorable outcome was defined as a modified Rankin Scale score of 3 to 6. The effect of ALP levels on FR was investigated with a logistic regression model.Of 788 patients who underwent thrombectomy, 277 achieved successful reperfusion. Among them, 142 patients (51.3%) failed to realize favorable outcomes at 3 months. After adjusting for confounding variables, higher ALP levels (p =0.002) at admission were independently associated with unfavorable outcomes at three months. Adding ALP values to conventional risk factors improved the performance of prediction models for FR.The current study found that the serum ALP levels at admission emerged as a potential biomarker for futile reperfusion in stroke patients undergoing thrombectomy. Further studies are warranted to confirm the clinical applicability of ALP level for futile recanalization prediction.Copyright© Bentham Science Publishers; For any queries, please email at epub@benthamscience.net.