A method is proposed for determining the compression-permeability (C-P) data expressed as the dependences of the local specific cake resistance and local cake porosity on the solid compressive pressure from a combined membrane filtration and stepped cake compression test. Filtration employing a membrane with a high flow resistance, which provided the pressure dependence of the average specific cake resistance, was followed by step-up compression, which gave cake porosities at several compressive pressures. On the basis of these data collected as the time variation of the dewatering volume, the compression-permeability data of bentonite slurry were evaluated. Consolidation behaviors of the filter cake and semi-solid material were accurately described on basis of the C-P data.