Abstract: A catheter (1) and vein repair method that enables vein repair surgeries without any bleeding and without hindering blood flow in veins through bypassing the blood flow in the vein to be operated and by preventing any diseases arisen due to stop of blood flow of the organ fed by the associated vein and that sustains blood flow by means of vein bypass in the course of vascular surgeries implemented for surgical processes related to veins in human body and that comprises one balloon (3) on each point close to its both ends, protective layer (4) positioned on the balloons (3); second path (5) enabling deflation inflation of the balloons (3), having monolithic pipe shape adhered to the first path (2) side by side, whose one open end terminates within the balloon (3); check valve apparatus (7) that is monolithic with back end of the second path (5) and provides substances such as air and liquid with the injector for inflation deflation of the balloon (3); protective segment (6) surrounding externally the first pat