Background: Cancers of the small bowel are rare. Diagnosis is late and difficult because of the lack of specific signs. Treatment is surgical. Prognosis is usually poor and depends on the histological type of tumor. Aim of Study: To specify the epidemiological, clinical and therapeutic characteristics of small bowel primary cancers in order to improve their prognosis. Material and Methods: This is a retrospective study about 20 cases of malignant tumors of the small bowel, collected in the department of general surgery of Habib Thameur Hospital in Tunis (Tunisia), from January 1994 through June 2011. Results: Our series involved 11 women and 9 men aged 62 on average (range: 44 - 80 years). In 45% of cases, the diagnosis was made in a patient rushed to hospital with clinical features of acute generalized peritonitis (66% of all surgical emergencies). Intestinal transit was performed in 5 patients only. Ultrasound abdominal examination was performed in 11 patients. Abdominal CT scan was performed in 7 patients, but the results were conclusive in 4 cases only (57%). Small bowel scanning was done in 5 patients only, but led to a positive diagnosis in all of them. All of our patients underwent surgery. Tumors of the small bowel were histologically divided as follows: carcinoid tumor (8 cases), leiomyosarcoma (7 cases), giant B-cell lymphoma (2 cases), malignant stromal tumor (2 cases) and malignant myxoid schwannoma (1 case). Malignant tumors of the small bowel most commonly arise in the ileum (60%) followed by the jejunum (35%). As for the long-term course, there was a recurrence at one year of a leiomyosarcoma and two recurrences of stromal tumors associated with liver metastases. Conclusion: Small bowel cancers are rare. Time to consultation is long and diagnosis is difficult and late due to the absence of typical presentation. Treatment is surgical and progression depends essentially on histological findings.