Curcumin is well known for its potent antioxidant activity. The result of numerous studies showed that antioxidants can protect against fluoride-induced toxicity. In the present study, protective effects of curcumin against sodium fluoride-induced toxicity in rat erythrocytes were evaluated. Curcumin (10 and 20 mg/kg) and vitamin C (10 mg/kg) were administrated intraperitoneally for 1 week followed by sodium fluoride (600 ppm) treatment for next week. Erythrocytes were isolated and superoxide dismutase and catalase activities as well as the levels of reduced glutathione, and lipid peroxidation were measured. The level of malondialdehyde in sodium fluoride treated rats (595.13 ± 20.23 nmol/g Hb) increased compared to the normal rats (315.44 ± 9.76 nmol/g Hb). Animals which were pretreated with curcumin at 20 mg/kg for 1 week prior to sodium fluoride intoxication showed significant reduction in the malondialdehyde level (320.22 ± 9.28 nmol/g Hb). Also, pretreated with curcumin (20 mg/kg) and vitamin C restored the superoxide dismutase and catalase activities and modified the level of reduced glutathione compared with control group (p > 0.01).