Deep venous thrombosis is 50 times less frequent in upper than in lower limbs. Data remain poor in the literature. Forty consecutive patients (24 males, 16 females, mean age: 54.5 years) were retrospectively analysed from 161 subjects who underwent venous explorations of the upper extremity for a 3.5 year period in the same center. Diagnosis of thrombosis was made by duplex ultrasonography (n =37) or phlebography (n =3). Main clinical manifestations were edema (n =36) and pain (n =29). Location of thrombosis was humeral (n =1), axillary (n =2), or sub-clavian (n =37, 2 bilateral). The majority of thrombosis (n =29) were secondary to cancer and venous catheter (n =19, 15 implanted ports), to central catheter alone (n =3) or cancer alone (n =7). The 11 others were associated with thoracic outlet syndrome (n =6) or apparent primary thrombosis (n =5). Thrombophilia was identified in 6 out of these 11. During follow up [mean of 9 months (0,5-36)], two patients developed pulmonary embolism, 14 a post-thrombotic syndrome and 16 patients died. Initial therapy included heparin (n =36) or fibrinolysis (n =4). Upper extremity deep venous thrombosis are mostly associated with cancers and venous catheters. Thrombophilia is frequent in the other cases. Heparin followed by oral anticoagulation is the optimal therapy whose duration depends upon underlying condition. Fibrinolysis has not been useful for preventing post-thrombotic syndrome in our study.