An apparatus for composite plating the inner surface of a cylindrical body, wherein a rod shaped electrode is inserted in a cylindrical body, composite plating liquid is made to flow upward in the annular space between the rod shaped electrode and the inner surface of the cylindrical body, and electric power is applied between the rod shaped electrode and the cylindrical body to composite plate the inner surface of the cylindrical body, comprises a baffle plate disposed above the cylindrical body to oppose an upward flow of the composite plating liquid out of the annular space.