Background/aims: Non-traumatic spontaneous intramural hematoma of the small intestine is a rare clinical condition, most commonly caused by over-anticoagulation. In this study, the clinical approach algorithm for patients diagnosed with a spontaneous isolated intramural hematoma of the small intestine associated with over-anticoagulation and the long-term outcomes of the patients are presented. Material and Methods: The records of patients who were diagnosed with intramural hematoma in 3 different medical faculty hospitals between 2007 and 2011 were retrospectively analyzed. After excluding patients with trauma history, hematoma in organs other than the small intestine, and with etiological factors other than over-anticoagulation, 15 patients with an isolated intramural hematoma of the small intestine were evaluated within the scope of the study. Results: The sites of first admission were emergency departments for 10 patients (66.6%) and other clinics for 5 patients (33.3%). Thirteen patients (86.6%) received medical treatment and two patients (13.3%) underwent surgical treatment. During the hospitalization period, a total of two patients (13.3%) died. Out of the 11 patients with an average follow-up of 22 months (range: 4-48 months), no patient had a relapse of intramural hematoma and three patients (27.7%) died due to reasons not related to intramural hematoma. Conclusion: Intramural hematoma diagnosis should be known by all physicians, because the site of first admission may be different clinics, since the clinical presentation begins with non-specific complaints. Early and accurate diagnosis by non-invasive methods will preclude unnecessary surgical interventions.