Oxidative stress, which plays an active role in the pathogenesis of various diseases, continues to be relevant in assessing the condition changes such as aggression. Some of Kangal dogs have been found to eat their own puppies during their first 24 hours following birth, as a case called maternal cannibalism. The present study aims to determine the levels of serum malondialdehyde (MDA), which is a product of lipid peroxidation, and serum glutathione peroxidase (GPx) and superoxide dismutase (SOD) enzymes, which are the parameters of antioxidant defense system, and total protein and albumin levels and to show their relationship with cannibalism. The study material consists of blood and blood serum of 30 Kangal dog breed in total, 15 of which have maternal cannibalism and 15 haven’t observed maternal cannibalism as a control group. Glutathione peroxidase, superoxide dismutase, malondialdehyde levels were investigated by means of spectrophotometric method in blood serum of these animals. The difference between the mean values of total protein, GPx, SOD, MDA and albumin was statistically significant in the results obtained. These findings conclude that oxidative stress and antioxidative metabolism plays a role in the pathogenesis of cannibalism in dogs.