The study of incidence of this disease and complications occurred at dogs was performed in the period January-December 2005. At the Clinics of Small Animals Diseases, the Facility of Veterinary Medicine of Belgrade, there were included 2.865 dogs of various breed and age categories. All the patients-suspects to have the babesiosis, on the basis of the clinical picture and the anamnestic information, were submitted to the complete haematological and biochemical blood analyses, as well as urine examination. There was also performed the blood smear, coloured by Romanowsky method. At 128 dogs, or 4.46%, there was established presence of Babesia canis and erythrocytes, which, along with the characteristic clinical picture, only confirmed the suspicion of existence of this disease. There was not established any breed inclination towards this disease, while most of the dogs (38%) were mix bred. As regards the haematological anomalies, there was registered anaemia (86.5%), eosinopoenia (32.1%), monocytosis (26.3%), leucocytosis (53.7%), and trombocytopoenia (68.3%). After the diagnosis has been established, all the dogs were subjected to a single treatment with Imisol (imidokarb dipropionate). Most dogs showed improvement of the general clinical state as early as the following day and finally, after two or three days of supportive therapy, the complete healing. However, there were some complications registered with 21 dogs (16.8%). All the dogs were 6-12 years old. The complications that most frequently accompanied the babesiosis of dogs, included the acute renal failure occurred at 8 dogs (38.0%), icterus and hepatopathy at 6 dogs (28.5%), acute respiratory distress syndrome at 3 dogs (14.2%), coagulopathy at 2 dogs (10.0%) and cerebral babesiosis at 2 dogs (10.0%). Out of this number, 16 dogs (76.1%) died despite the administration of the adequate therapy.