A new type of microreactor for fine particle production was developed to achieve stable continuous production, precise control of particle properties (such as particle size, distribution, and shape), and high throughput. The proposed microreactor, the annular multi-lamination microreactor, had an annular five-layer structure in a column at the center of the microreactor. By utilizing the microreactor, the crystallization of fine silver halide particles was examined under various operational conditions. From these results, optimum structures and operation methods for the high-throughput production of fine particles. which do not cause clogging of the microchannel, were determined. In addition, we give a simple method of equaling-up for industrial production. Thus, it is expected that the concepts of design, operational method, and equaling-up shown here can be incorporated into practical microreaction technology in the industrial field of fine particle production.