[Problem] Objects of the invention are to provide a cable assembly with reduced characteristic impedance at a protruding end portion of a first wire of a cable and configured for easy manufacture, and to provide a method for manufacturing the cable assembly. [Configuration] A cable assembly A1 includes a terminal 400a, a cable 100, and an electroconductive member 200. The cable 100 includes an outer insulator 100, a shield conductor 120 inside the outer insulator 110, and at least one first wire 130a being a signal wire inside the shield conductor 120. The first wire 130a includes a protruding portion Pa protruding in the Y-Y' direction from the shield conductor 120 and the outer insulator 110. The electroconductive member 200 is an electroconductive plate or electroconductive tape wound around at least a part in the Y-Y' direction of the protruding portion Pa.