We have devised a non torque, supple and flexible catheter with a Ball-tip and have applied this catheter (combined) with the plastic coated guide wire in a superselective angiography to a total of 43 patients, namely, 41 hepatic and 2 renal tumor patients. Since the pulling forces of the arterial blood flow carries the Ball-tip supple catheter to the distal part of the desired artery, the new system seldom causes spastic change and subintimal injury. We have achieved successful catheterization and embolization in all but one cases, even when there are extensive curves in the arteries leading to the affected site. Our conclusion is that cases which cannot be embolized by the conventional method due to the extensive curves of the artery can be safely treated by using this catheter system.