To provide a method for producing an inorganic plate which exhibits no discoloration and a good yield and does not hurt a production apparatus by preventing excessive drying.

A wet mat to be a lower layer part 11 is obtained by a wet process. On the upper surface of the mat, a mixture for an intermediate layer part 13 is spread and deposited. In addition, on the mixture is mounted a wet mat to be an upper layer part which is obtained by a wet process using a kind of slurry consisting of mineral fibers, a kind of inorganic powder, and a binder and has a width nearly equal to that of the wet mat to be the lower layer part 11 to obtain a laminate 10. Next, with both side fringe parts 11a, 12a of the wet mats to be the upper and lower layer parts 11, 12 overlapped directly, the laminate 10 is pressed and integrated. After the laminate 10 being heat-dried, both side fringe parts 11a, 12a of the laminate 10 are cut off.