Abstract Stroke is one of the most important diseases that seriously threaten the health and public health of elderly patients.NSUN2 refers to the predominant methyltransferase for RNA m5C methylation, contributing to increased RNA stability, translocation and translation, and playing an important role in the physiopathology. However, there is insignificant progress on the biological functions and mechanisms of NSUN2 in cerebral ischemia-reperfusion injury. Here, C57BL/6 mice were employed to establish a middle cerebral artery ischemia-reperfusion injury model (MCAO) and found to significantly increase in NSUN2 protein and mRNA expression levels by Western blotting and qRT-PCR. Subsequently, NSUN2 knockout mice were exploited to build the MCAO model. This study reported that knockout of NSUN2 significantly aggravated brain infarct size and behavioral scores, while reducing 7-day postoperative survival and increasing neuronal apoptosis and injury in MCAO mice. According to the investigation of Western blotting results, decreased PI3K/AKT, ICAM-1 and Bcl-2 protein expressions and increased apoptosis-related protein (Caspase-3/Bax) were found. Overall, this study suggested that NSUN2 may affect cerebral ischemia-reperfusion injury via PI3K/AKT signaling channel and ICAM-1 protein regulation of apoptosis.