Introduction: Understanding the natural history and prognostic factors associated with disease recurrence and survival of resected small bowel GIST is necessary to appropriately select patients for adjuvant therapy. Methods: Oncologic outcomes of 69 patients with primary small bowel GIST surgically treated between 1976 and 2004 at a single institution were reviewed. Prognostic factors analyzed included age, gender, tumor site (duodenum, jejunum, ileum), extent of disease at presentation (local, locally advanced, metastatic), type of resection (R0, R1, R2) and pathologic characteristics. Tumors were assigned risk levels (high, intermediate, low, very-low) on the basis of size and mitotic rate according to current NIH (National Institutes of Health) recommendations. Results: Mean patient age was 59 years with 46 men. Median follow-up for survivors was 61 months. Tumors were most frequently found in the jejunum 52% (36) followed by the ileum 25% (17) and the duodenum 23% (16). Ninety-nine percent of patients had a R0 resection of their primary tumor. Sixty-seven tumors (99%) were c-KIT positive. There were 59% high-, 19% intermediate-, 16% low-, and 6% very low-risk GIST. Local and distant recurrences occurred in 3 and 30 patients, with median time to event of 31 months and 16 months, respectively. In patients with very-low or low-risk GIST no local or distant recurrences or disease-specific mortality was observed. Among patients with high- and intermediate-risk GIST, 5-year distant disease-free survivals were 27% and 61%, respectively. The 5-year disease-specific survivals for these two groups were 26% and 71%, respectively. In a Cox analysis, NIH pathological classification was the only independent prognostic factor associated with disease-free and disease-specific survival. Conclusion: High-risk small bowel GIST have a significantly higher risk of disease recurrence and poorer survival despite complete surgical resection. These patients should be routinely considered for adjuvant therapy with a tyrosine kinase inhibitor.