Spontaneous splenic rupture is a quite rare entity that may develop secondary to some special situations (lymphoma, post-abdominal surgey etc). In the literature, the case of a patient has been reported following thoracic surgery. In a patient who had undergone right upper lobectomy for pulmonary carcinoma, signs of acute abdomen and low levels in the hemogram were detected on the fifth postoperative day; therefore, the patient underwent further investigations. A radiological evaluation revealed splenic rupture, and the patient was operated on. A case is presented that may be fatal and requires emergency response and that has to be kept in mind, although it is extremely rare. A case of spontaneous splenic rupture has been presented that may be fatal and requires emergency response; this should be kept in mind, although it is extremely rare.