The authors discuss diagnostic difficulties that may occur in the interpretation of splenomegaly. In some cases, other tumorous formations, palpable in the left hypochondrium (renal tumor and retroperitoneal fibroma in cases demonstrated) may be taken for splenomegaly. In other cases, diagnostic difficulties may be related to establishing the cause of genuine splenomegaly. Out of 10 patients with genuine splenomegaly, the cause of which could not be ascertained at the prehospital stage, the enlargement of the spleen in 2 was due to liver cirrhosis, in 3, to subleukemic myelosis, in 1, to splenic tuberculosis, in 2, to multiple capillary angiomas of the spleen, in 1, to chronic monocytic leukemia, and in 1 patient, to splenic echinococcosis. In 3 patients out of the 10, the diagnosis was verified by surgery followed by histological examination of the spleen. The conclusion is made about the necessity of the use of clinical and laboratory examinations, of patients with obscure "splenomegaly" together with the use of x-ray and ultrasonography of the spleen, kidneys, gastrointestinal tract, puncture of the bone marrow and spleen. In some cases, splenectomy may be performed along with histological examination of the spleen as the final stage of differential diagnosis of splenomegalies.