The 10-year-old dog of the Cane Corso Italiano breed was referred for clinical examination due to abdominal distension, weakness, and pale mucous membranes. Laboratory blood tests revealed regenerative anemia. Abdominal ultrasonography identified a large heterogeneous lesion occupying a large part of the abdominal cavity, which exerted a mass effect. The owner consented to contrast-enhanced computed tomography (CT) examination of the abdomen and thorax. CT scan revealed a heterogeneous, hypodense, well-demarcated mass containing multiple fluid spaces. It was revealed that the mass originated from the spleen and showed no tumor metastases. Based on clinical and imaging examination, a decision was made to perform a midline laparotomy with splenectomy. After splenectomy the spleen, along with a spherical mass was submitted for histopathological examination. No presence of neoplastic cells was noted in any of the samples assessed, which provided the basis for a definitive diagnosis of splenic haematoma (haematoma lienis)