In order to solve the problems of serious damage of micronized diamond during brazing and poor bonding between brazing material and substrate. A suitable brazing method was used to braze micronized diamond (325/400#) on a steel substrate. The bonding interface was analyzed and a grinding head was prepared to process the alumina ceramic plate. It was found that the micronized diamond abrasive grains were less damaged. The products at the interface between the steel substrate and the brazing material are γ-phase solid solution formed by Fe and Cr and Ni-Fe replacement solid solution formed by Fe and Ni. The presence of solid solution ensures a strong bond between the brazing material and the substrate. The prepared brazed micronized diamond grinding heads have a high service life when processing ceramic plates.