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The repetitive contraction of the myotube has been measured by the local movement of micro-markers on the thin film of the scaffold during the electric stimulation <em>in vitro</em>. The scaffold is made of the thin polydimethylsiloxane film (6 μm thickness), of which the back side has an arrangement of micro-protrusions (4 μm diameter, 2 μm height, and 30 μm interval) made using the photolithography technique. Mouse myoblasts (C2C12) were seeded on the film at the counter surface to the protrusions at the density of 50000 cells/cm². The cells differentiated on the scaffold into myotubes over 12 days in a medium containing 10% FBS (fetal bovine serum) and 1% penicillin/ streptomycin in the incubator. The electric pulses (30 V amplitude, 1 s pulse cycle, and 1 ms pulse width) were applied between electrodes of titanium wire dipped in the medium. The contraction of the myotube was observed by a microscope through the transparent scaffold. The experimental results show that the amplitude of the cyclic variation of the distance between micro-markers relates to the distance and the alignment. The designed scaffold can be applied to analyze the local contractile movement of the layer of myotubes <em>in vitro</em>.