A method for making diatomite bricks belongs to the technical field of inorganic non-metallic materials. The invention consists of materials: natural diatomite, kaolin, attapulgite, sepiolite powder, vermiculite powder, bentonite, water, bamboo powder, alginate, silicon carbide, and carboxymethyl cellulose. Diatomite bricks are prepared through the production process of configuring materials, pouring molds into billets, and microwave drying and sintering. The microwave drying and sintering method adopted in the present invention has fast heating speed, improved production efficiency, uniform heating, shortened production cycle, high efficiency, energy saving and no pollution. The diatomite brick produced by the invention is environmentally friendly and non-toxic, and has the functions of eliminating formaldehyde, purifying air, adjusting humidity, releasing negative oxygen ions, preventing fire and flame, sterilizing, deodorizing, absorbing moisture and deodorizing, absorbing sound and reducing noise.