This study aims to evaluate the protective effects of ω-3 fatty acids (FAs) on doxorubicin (DOX)-induced hepatotoxicity and nephrotoxicity in rats. A total of 24 adult male Sprague Dawley rats were divided into three groups. Control group was given only saline by intragastric gavage. DOX group received DOX at the dose of 30 mg/kg intraperitoneally on day 28. DOX-ω-3 FA group was given as ω-3 FAs at the dose of 400 mg/kg daily by intragastric gavage for 30 days and received DOX at the dose of 30 mg/kg intraperitoneally on day 28. At the end of the 30-day experimental period, the serum, liver and kidney tissue specimens were taken from the animals by giving a general anesthesia. Glutathione (GSH) and malondialdehyde (MDA) levels in serum and GSH and MDA levels and superoxide dismutase (SOD) and glutathione peroxidase (GSH-Px) activities in liver and kidney tissues were measured spectrophotometrically. In our study, a significant increase in MDA levels was observed in rats when given a dose of DOX and a significant decrease in the levels of GSH, SOD and GSH-Px activities in serum, liver and kidney tissues was determined when compared with control group. In addition, a significant decrease in MDA levels was observed in rats when a dose of ω-3 FAs was given with DOX and a significant increase was determined in the levels of GSH, SOD and GSH-Px activities in serum, liver and kidney tissues, when compared with DOX group. We concluded that ω-3 FA had favorable effects in rat liver and kidney tissues by preventing oxidative damage.