In this paper, it was described 3,5 years old, male, Bull Terrier breed a dog which was came to our clinic with anamnesis such as intermittent fever, weakness, depression, become dull in hairs, hyperemia in scrotum and nasal discharges with blood. It was determined hepatomegaly, splenomegaly, lymphadenopathy and paleness of mucous membranes in clinical examination. In addition to hematological abnormalities including trombocytopenia (40 mm/103) and anemia, İt was determined that β hemolytic streptococci colonies (103) reproduced in urine culture, serum total protein (9.4 g/dl). globulin (6.3 g/dl), urea (181 mg/dl), kreatinin (4.7mg/dl) levels increased and aibumin (3.1 g/dl) level decreased in blood examination. Ehrlichia canis antibody titration 1/40 in ratio was found by used indirect fluorescent antibody (IFA) test. When clinical and laboratory sings such as hematological, biochemical and microbiological were considered, the case was diagnosed of chronic Ehrlichiosis, Doxycilyn (20 mg/kg) and sulfonamide-trimethoprim (30 mg/kg) were used twice a day during three weeks as oral for treatment. The dog that Ehrlichiosis was firstly determined in our country was entirely treated with drugs.