Objective To investigate whether remote ischemic preconditioning (RIPC) exerts a neuroprotective effect against hypoxic ischemia by decreasing neuronal DNA methyltransferases (DNMTs) levels via plasma exosomes. Methods C57BL6 mice were RIPC with simultaneous tail vein injection of the exosome inhibitor GW4869, and 1 hour later, middle cerebral artery occlusion (MCAO) was performed, and the mice were randomized into four groups. Bederson score and cornering test to assess the degree of neurologic impairment. Expression levels of DNA methyltransferases (DNMTs) and nerve damage-related genes in the mouse cerebral cortex using real time PCR and Western blot. Plasma exosomes were extracted from mice before and after RIPC, and co-cultured with mouse neuronal cells HT22 for Oxygen glucose deprivation (OGD). Detection of cell viability by CCK8. The cell morphology and the fluorescence intensity of the anti-apoptotic protein Bcl-2 were observed by immunofluorescence, and the mRNA and protein expression levels of DNMTs and related apoptotic genes (Caspase-3, BAX, and Bcl-2) were detected in the cells. Results The results of Bederson scores and cornering experiments showed that RIPC intervention significantly improved neurological deficits after MCAO in mice, and its neuroprotective effect was significantly attenuated after the administration of GW4869. RIPC treatment down-regulated the expression of DNMTs, Caspase-3 and BAX and up-regulated the expression of Bcl-2 in the cerebral cortex of MCAO mice. In vitro results showed that RIPC-derived exosomes reduced the expression of DNMTs, enhanced the fluorescence intensity of Bcl-2 and improved cell morphology in HT22 cells under OGD conditions, while down-regulating the expression of Caspase-3 and BAX and enhancing cell viability. Conclusion RIPC may play a neuroprotective role by downregulating the expression of DNMTs through plasma exosome-mediated manner and inhibiting the expression of Caspase3 and BAX, increasing the expression of Bcl-2, inhibiting neuronal apoptosis, and enhancing the tolerance of neuronal cells to the hypoxic-ischemic environment.