Abstract: A microreactor having a reaction mixture inlet, a reaction mixture channel, and a reaction mixture outlet is provided, in which a piezoelectric material that generates surface acoustic waves and has, formed on the surface thereof, a thin film having catalytic activity is disposed in the reaction mixture channel so that the inner surface of the reaction mixture channel is configured from the thin film. The thin film having catalytic activity can be constituted of a material selected from a group consisting of metals, metal oxides, and complexes of organic compounds. The microreactor attains remarkable improvements in the effect of stirring a reaction mixture and catalysis, whereby a chemical reaction can be evenly and efficiently accelerated. The microreactor is free from channel clogging and pressure loss and hence renders a stable and precise chemical reaction possible.