An apparatus for guiding a biomedical electrode is provided, which guides a biomedical electrode to be brought into close contact with a living body surface of a voluntary muscle into optimum close contact positions on the basis of positions of the voluntary muscle and a neuromuscular junction of the voluntary muscle inside the living body surface. The relative positions of the voluntary muscle and the neuromuscular junction of the voluntary muscle to the living body surface are detected from muscle action potentials detected by myoelectric detection electrodes put into close contact with a large number of positions on the living body surface. On the basis of the relative position information, a close contact position of the biomedical electrode to be brought into close contact with the living body surface of the voluntary muscle is guided to an optimum position.