The invention relates to an automatic slurry spreading device and method for the bottoms of ceramic unburied bricks. The device comprises an unburned brick conveying mechanism for slurry spreading with a rubber roll embossing machine, and a bottom slurry cylinder and a bottom slurry transfer cylinder are sequentially arranged beside the rubber roll embossing machine. A second bottom slurry pump arranged in the bottom slurry cylinder communicates with the rubber roll embossing machine through a slurry feeding hose. A first bottom slurry pump is arranged in the bottom slurry transfer cylinder, aglaze discharging pipe communicating with the first bottom slurry pump stretches into the bottom slurry cylinder, and the bottom slurry cylinder and the bottom slurry transfer cylinder are provided with a cooling circulation system. The rubber roll embossing machine communicates with the bottom slurry transfer cylinder through a slurry returning pipe, and residual bottom slurry is recovered intothe bottom slurry transfer cylinder. The first bottom slurry pump and the second bottom slurry pump are each provided with a slurry feeding pipe and a stirring mechanism located at the end of the corresponding slurry feeding pipe. The bottom slurry is evenly spread on the bottoms of the unburned bricks through a rubber roll, uniformity of the slurry spreading thickness is achieved through adjusting equipment, the situation that the bottom slurry is prone to sediment, caking and concentration instability because the temperature of the glaze slurry is increased in the long-time circulation process is effectively prevented, and the situation that the slurry spreading uniformity is influenced by non-uniform mixing concentration of original bottom slurry glaze and the recovered glaze slurry isprevented.