A wire material for a canted coil spring includes a core wire composed of a steel having a pearlite structure, a copper plating layer covering the outer peripheral surface of the core wire, the copper plating layer being composed of copper or a copper alloy, and a hard layer disposed adjacent to the outer periphery of the copper plating layer, the hard layer having a higher hardness than the copper plating layer. The steel constituting the core wire contains 0.5% or more by mass and 1.0% or less by mass carbon, 0.1% or more by mass and 2.5% or less by mass silicon, and 0.3% or more by mass and 0.9% or less by mass manganese, the balance being iron and unavoidable impurities.