Venous gangrene of the upper extremity is a rare entity and is the result of massive occlusion of all venous outflow of the extremity. The syndrome is strongly associated with hypercoagulable states including malignancy, low cardiac output states, and hereditary or acquired hematological abnormalities. Diagnosis can be straightforward but must be made early in the course of the process for treatment to be effective. Treatment has historically produced only modest results, and patients continue to suffer a high morbidity and mortality. We present a series of 6 patients with venous gangrene or impending venous gangrene of the upper extremities--a relatively large series. Two patients suffered from malignancy, 3 patients suffered from low-flow cardiac states, and 1 patient suffered from an overdose of calcium channel blockers. Hematological abnormalities included heparin-induced thrombocytopenia and thrombosis in 3 patients, activated protein C resistance in 1 patient, and lupus anticoagulant in 1 patient. Three patients experienced other major venous thrombotic complications, two of whom died (renal and cerebral venous infarction). Venous gangrene of the upper extremity remains a rare occurrence but one in which early identification and intervention may lead to improved outcomes.