The present study assessed whether the protective effects of curcumin against cerebral ischemia injury were due to the suppression of overactivated autophagy. Curcumin is a well-known natural polyphenolic compound that effectively counteracts oxidation, inflammation, and various types of cancer. Several studies have demonstrated the protective effects of curcumin against ischemia-reperfusion injury in tissues from the lungs, cardiomyocytes, and liver. The present study employed brain injury models induced by middle cerebral artery occlusion (MCAO) in rats and PC12 oxygen-glucose-deprived (OGD) cells. Infarct area, neurological score, lactate dehydrogenase (LDH) activity, autophagy expression, cell apoptosis, and mRNA and protein expressions of caspase-3 were determined following curcumin supplementation. Compared to MCAO rats, curcumin-treated MCAO rats exhibited substantial reductions in neurological score, infarct area, and LDH activity. MCAO also increased LC3 II/I protein expression and decreased p62 protein expression, but curcumin supplementation significantly reversed these altered protein expressions. Caspase-3 protein expression increased by 46.2% in the MCAO group, but curcumin supplementation significantly reduced this expression. Similarly, apoptosis increased by 33.1% in OGD cells, but curcumin supplementation significantly reduced apoptosis to 21.6% and 9.3% at doses of 100 and 200 mg/kg, respectively. The mRNA and protein expressions of caspase-3 exhibited substantial increases in OGD cells but these expressions were significantly decreased following curcumin supplementation. Taken together, the present results indicate that curcumin represents a natural bioactive substance that can protect against cerebral ischemia via the suppression of overactivated autophagy.