Disclosed is a microstructural plasma device based on a printed circuit board process. A microcavity of the device is composed of an upper electrode, a middle medium layer and a lower electrode. Each unit of the device is driven by the upper electrode and the lower electrode. A substrate is made of insulating medium epoxy resin materials. Two layers of copper foil are manufactured on the upper surface and the lower surface of the substrate. Certain safe distances are reserved between the edges of the layers of copper foil and the edge of the substrate. The cylindrical microcavity semi-through hole units are arranged in an array mode. Microcavity semi-through holes just penetrate through the upper electrode and do not penetrate through the middle medium layer and the lower electrode. In the array, the distances between rows are not smaller than those between columns. The two layers of copper foil which are separated by the substrate are used as the upper electrode and the lower electrode, the two electrodes are respectively led out of amphenol connectors, and the coplanar-type microstructural plasma device based on the printed circuit board process is obtained.