The invention relates to a microporous filter plate to be used in a suction drier, particularly in a capillary filter, the filter plate of which contains a membrane with a mean pore size of about 1 micrometer, a substrate, whereon the membrane is positioned, and a recessed area in the interior of the filter plate with cavities for a filtrate and for a backwash liquid. According to the invention the recessed area in the interior of the filter plate is provided with supporting elements, in which the ratio between the longest dimension and the shortest dimension is in maximum 1.5 in the cross-section parallel to the filtration surface of the filter plate, for allowing liquid to flow essentially simultaneously and easily in all directions and for the structure of the filter plate being durable for stresses based on pressure peaks.