Ischemic wounds unresponsive to standard treatment in thromboangiitis obliterans are associated with amputation, morbidity, and mortality. In this study, hyperbaric oxygen therapy was added to standard treatment of 36 patients with thromboangiitis obliterans with ischemic ulcerated wounds in the extremities. Full recovery was observed in 52.7% of cases (25% at discharge, 27.7% during follow-up). Resting pain after treatment decreased significantly compared to pretreatment levels based on visual analog scale scores (7.1 +/- 1.7 vs 2.2 +/- 3.0, P = .0001). Mean wound area also decreased significantly after treatment (22.6 +/- 17.5 vs 13.02 +/- 16.5, P = .0001). The number of patients requiring no assistance during routine daily activities increased significantly (25% vs 55.5%, P = .001). All patients were at Fontaine stage IV before hyperbaric oxygen therapy. The number of patients at stage IIB increased significantly after treatment, while that of patients at stage IV decreased significantly (0% vs 47.2%, P = .0001, and 100% vs 47.2%, P = .0001, respectively). None of our patients was able to walk without pain before treatment; however, walking distance was significantly extended in 16 patients who were capable of walking (0 vs 190.6 +/- 129.4 meters, P = .0001). In addition, 11.1% of patients underwent major amputation during follow-up.