PURPOSE: To obtain a mechanochemical element with a high response speed by sealing airtightly a polymer gel layer, a polarized layer and an outer electrode layer by using a pliable polymer film together with an electrolytic solution.

CONSTITUTION: An extremely fine fibrous inner electrode 2 is wound around a fibrous polymer gel 1, and these windings are bundled to constitute a polymer gel layer. This polymer gal layer has one end of the inner electrodes 2 connected to a concentric polar line connected to an electrode lead-out part 7 on an activation part side. Consequently, the ion is rapidly spread in the gel fiber, if a direct current is applied to the polymer gel, because the electrode fiber is always directly kept in contact with the gel fiber. In addition, during the expansion and contraction of the gel fiber by an applied voltage, the gel fiber is always concentric into a central direction as the expansion coefficient of the gel fiber into an axial direciton is high. Therefore, the coil-like inner electrode 2 expands in the axial direction easily, coming into contact with the surface of the gel tightly. Thus, the inner electrode 2 can withstand a cut due to bending. Further, this mechanochemical element, if miniaturized, converts energy efficiently as it has an extensive area due to the fibrous electrode, so that the element can be applied to a micromachine.