To miniaturize the whole of a chemical reaction apparatus in which e.g. a desired fluid substance is generated through a catalytic chemical reaction of a fluidized mixed material with a catalyst arranged in a minute passage.

In the apparatus, a first, second and third substrates 1-3, respectively, are laminated in order, and a wound minute passage 11 is formed in the surface of the substrate 2 opposite to the surface of the substrate 1. A catalyst layer is disposed in the passage 11. An oxidant injector 13 is arranged in the vicinity of one end of the passage 11, and the injector 13 consists of so-called a piezo jet or a static jet injector which injects a liquid from ultra-minute nozzles in particle form with the amount of injection controlled. A specified liquid is supplied automatically from a small liquid (oxidant) storage vessel through capillarity to the injector 13.