Background: This study aims to determine the prevalence and characteristics of symptomatic upper extremity deep venous thrombosis (UEDVT) and its association with symptomatic pulmonary embolism (PE) in a tertiary care hospital. Methods: Between January 2001 and December 2003, the prevalence of symptomatic UEDVT at a university hospital within the past three-years was evaluated retrospectively. Patients were identified by hospital records, and a computerrecorded list of all color Doppler ultrasonograms, venograms,and magnetic resonance angiograms of upper extremities was also used. Data were obtained from medical records and follow-up patient questionnaires. Results: Symptomatic UEDVT was diagnosed in 91 of 100.942 patients of all ages (0.09%) [or 89 of 70.751 of adult patients ?20 years of age; 0.13%]. Seventy three (80%) of 91 patients with UEDVT had multiple risk factors; 33 patients (36%) had malignancy, 34 patients (37%) had central venous catheters (CVCs), peripheral venous lines (PVLs) and cardiac pacemaker (n=1), 36 patients (40%) had chronic disorders (chronic obstructive pulmonary disease, cardiac disease, chronic renal failure with hemodialysis), 12 patients (13%) had trauma or surgery, 13 of 53 patients (24%) had UEDVT secondary to thrombophilia. Symptomatic PE developed prior to thrombosis being treated in 32 patients (35%). All patients received anticoagulant therapy except 13 patients (5 with thrombolytic therapy; 8 with thrombectomy) who were treated with other methods initially. Conclusion: Upper extremity deep venous thrombosis is not a rarely seen pathology. Its etiology is usually multifactorial and secondary to thrombophilia, CVC, PVL, chronic diseases and cancer. As PE resulting from UEDVT is a common complication, patients with risk factors should be diagnosed and treated early.