Provided is an electrode capable of increasing a degree of freedom in machining shape with a simple structure, an electrochemical machining apparatus using the electrode, an electrochemical machining method, and a product machined by the method. An electrode 4 has a core tube 41 formed of a material by which a second hole 101b having a direction or a curvature different from that of a first hole 101a having a predetermined curvature can be formed continuously from the first hole 101a and a coating 42 fixed to an outer periphery of the core tube 41.