A secondary coil for a linear motor, which is a composite metal plate comprising a backing metal layer 1, an intermediate bond metal layer 2 and a surface metal layer 3 which are integrally connected, the intermediate bond metal layer being formed of aluminum or aluminum alloy, the surface metal layer being formed of copper or copper alloy having a thickness of 2 to 8 mm. A copper plate or a copper alloy plate for the surface layer and an aluminum plate or an aluminum alloy plate for the intermediate layer are placed on each other and connected by rolling. The surface-layer metal plate with the bond layer is placed on a metal plate for the backing metal layer, with the bond layer being contacted with the metal plate for the backing metal layer, and two plates are connected by rolling.