The aim of this study is to identify the causative protozoan parasites infecting dogs in Egypt by discussing the clinical signs, hemato-biochemical, oxidative stress, and the pro-inflammatory markers alterations in Canine leishmaniosis (CanL). A total of 100 dogs of different breeds were collected from January to December 2020. The age of the dogs ranged between 3and 10 years. All the 100 dogs suffered from signs compatible with vector-borne diseases. Only one reported case was recorded for infection with CanL from 100 examined dogs (1% infection rate). The dog was 7 years old female German Sphered dog with significant weight loss, depression, pyrexia (temp= 40º), lameness on hind limbs, severe respiratory manifestations, and skin ecchymosis in the ventral abdomen, tail, and hind leg with lymphadenopathy. It had marked leukocytosis, neutrophilia, and monocytosis. Normocytic normochromic anemia and thrombocytopenia were also observed. The most important biochemical changes in the serum were mild hyperproteinemia, hypoalbuminemia, hyperglobulinemia, elevated liver and kidney function, elevation in C-reactive protein and malondialdehyde level and reduction in total antioxidant capacity.