Incidence, clinical findings, etiology and evolution of 25 cases of deep venous thrombosis of the upper extremity are evaluated in a group of 23 in- and outpatients. The incidence of the disease represents less than 6% of all deep venous thromboses. The most frequent etiology among outpatients was "primary" deep venous thrombosis. The percentage of pulmonary embolism was 8%. The prognosis is favourable in 90% of cases.