[Problem] To provide: a wire harness capable of suppressing an increase in the mass of the wire harness itself and improving routing layout freedom while reducing electromagnetic noise; and an electromagnetic wave suppression member. [Solution] A wire harness equipped with electric wires 2 and an electromagnetic wave suppression member 8 provided around the periphery of the electric wires 2, wherein the electromagnetic wave suppression member 8 is equipped with: a restriction member 81 provided so as to cover the outer circumference of the electric wires 2, and having an inner wall section 81athat is harder than are the electric wires 2; and a ring-shaped magnetic core 82 comprising a nanocrystalline soft magnetic material and provided around the periphery of the inner wall section 81a.