PURPOSE: This investigation was to evaluate the efficacy of catheter-directed thrombolysis with urokinase in treating symptomatic deep vein thrombosis (DVT). METHODS: Eight patients with DVT underwent treatment for 8 affected limbs. The average urokinase dose was 487.5 million IU (range, 1.5 million to 6.5 million IU) infused over an average of 48 hour (range 24~72 hours). RESULTS: Lysis was complete in 5 (63%), and partial in 2 (25%), not achieved in 1 (12%). One chronically occluded proximal iliac vein through popliteal vein antegradely and tibial vein through internal jugular vein retrogradely could not be crossed with a guide wire. Angioplasty (n=3) and stent placement (n=1) were applied in three limbs with underlying venous stenosis. One limb among three limb of initial complete lysis was detected thrombus at femoral vein but this patient was asymptomatic at 6 month later. There were no major complications or clinically detectable pulmonary emboli. CONCLUSION: This initial experience suggests that catheter-directed thrombolysis with urokinase for treatment of symptomatic DVT is safe and effective.