This work investigated the effects of food additives on the oxidative stress markers and liver marker enzymes. Food additives are products added to the basic food stuff with an aim of improving its flavor, aspect, texture, color, taste, and value. Thirty (30) Wistar rats were divided into five groups of six rats each. Group A received a daily dose of distillated water and normal rat pellet, Group B, C, D and E received 20 mg/kg body of Aspartame, Sodium Benzoate, Sodium nitrite and sodium sulfite respectively. The duration for exposure of these animals to food additives was 30 days and the groups were observed daily for general conditions. At the end of feeding the animals, blood samples were collected and analyzed. The result of the analysis showed that ALT significantly (p<0.05) increased with sodium nitrite and sodium sulfite while ALP increased significantly (p<0.05) with sodium sulphite. The oxidative stress biomarker, catalase showed a significant increase with sodium benzoate and sodium sulphite. The results revealed that the food additives are injurious to the animals. The toxicity of the food additives studied at 20 mg/kg are in the order of Sodium nitrite > Sodium benzoate > Sodium sulphite > Aspartame.