The oxygen consumption of single contractile myotubes was investigated by amperometric monitoring of the reduction current for oxygen using scanning electrochemical microscope (SECM) equipped with Pt microelectrode. The contraction of myotubes was induced by the application of electric pulse stimulation. The reduction current for oxygen immediately decreased after application of the electric pluses with 1.0 Hz and almost reached steady state because the activity of the oxygen consumption by respiration increased due to the contraction of myotubes accompanied with a consumption of energy.