Canine dermatological problems chiefly of bacterial etiology are among the most commonly seen disorders in canine practice that may lead to increased risk of oxidative stress. This work aimed to study the relationship between antioxidant trace elements (Zn-Cu and Se) and oxidative stress in dogs affected with pyoderma. This clinical study was applied on 31 dogs, 20 dogs used as control and 11 dogs affected with pyoderma to determine hematological, biochemical, histopathological and antioxidant trace elements alterations. Results from infected dogs showed leukocytosis accompanied by neutrophilia and lymphpenia. Along with statistically significant decrease in Plts and insignificant decrease in (PCV) %. Affected dogs also showed presence of hypothyroidism as demonstrated by reduced levels of free T4 and TSH. Along with statistically significant increase in the cortisol level. Hyperadrenocorticism were the most recorded haemato-biochemical alterations. The antioxidant trace elements indicated statistically significant decrease in selenium level (Se) together with insignificant decrease in zinc level (Zn). The study revealed that pyoderma infection represents a stress factor against dogs affecting their antioxidant trace elements, consequently antioxidant defense system.