The purpose of these research was to analyze the haemogram in dogs with haemangiosarcoma lienis. Anlyzing haematogram, erithrogram and leucogram, history of the patient, clinical signs, can be helpful in getting define diagnosis and prognosis of the disease. Haemangiosarcona (HS) is often disease nowadays in dogs in urban enviroment. Also, we have availabele a lot of diagnostical methods and approachies in other to define the exact diagnosis and eventual prognosis. The group of examinated dogs compraise a different patients with various clinical signs. The owners describe the different clinical signs of the dogs, that depend of the progress and stage of disease. All of the dogs, after the different analyses has diagnosed haemangiosarcoma lienis. Values of parametres can indices the appearance of haemangiosarcoma lienis. Dogs with splenoctomy of rupture haemagiosarcoma, has bad prognostic signs. During the period of 8-12 month, mild leukocitisis developed, subfebrile status and exacerbation of the disease with generalise methastatic tumors in the different parts of the body. There are a lot of local contact tumors.