A repair lining for a heat exchanger tube includes a sleeve having ends. A tubular basic body is disposed in the sleeve and has ends protruding beyond the ends of the sleeve. One of the ends of the basic body has a top part being supported on the sleeve and the other of the ends of the basic body has a thread formed thereon. A nut is disposed on the thread for bracing the repair lining in the heat exchanger tube. At least one clamping ring is disposed on one of the ends of the basic body between the sleeve and the top part, and at least one clamping ring is disposed on the other of the ends of the basic body between the sleeve and the nut. The clamping rings have a conical shape in an initial relaxed condition being changed into a flattened shape with an enlarged diameter by relative motion between the basic body and the sleeve. A method for repairing a heat exchanger tube with a repair lining includes introducing a repair lining into the heat exchanger tube, and tightening the nut with a tool for axially enlarging the clamping rings and substantially fluid-tightly connecting the basic body to the heat exchanger tube.