The present invention relates to a balloon catheter system for sealing puncture points or openings in body cavities, hollow organs or in percutaneous drainage operations in mammals, consisting of a filling catheter on the distal end of which a first balloon can be filled with the filling medium is arranged with a further balloon arranged proximally spaced apart therefrom. The balloons close the puncture point or the opening on the two sides in the filled state of the balloon. A hollow needle open at the shaft or the shaft end can be guided in the lumen of the filling catheter for filling the two balloons with the filling medium, wherein the shells of the two balloons enclose the shaft of the filling catheter. The filling catheter in each case has an opening arranged in the balloon lumen to fill the two balloons.
