In this work, we studied the dry pressing technique for making porous supports with average pore sizes about 1 mu m. Emphasis was placed on the microstructure characterization of pores, which included porosity, pore size and tortuosity. The relationship between these porous characteristics and other properties such as specific permeability and flexural strength were also investigated. The tortuosity values, which were determined by a dynamic water expulsion method, were considered as reasonable indicators for pore connectivity and fell in the range of 2.5 to 3.5 for our samples. The tortuosity would increase with increasing forming pressure, which suggested that under a higher forming pressure the particles would be packed more closely and therefore making the flow path more tortuous. Finally, our results seemed to indicate that the three porous characteristics, i.e., porosity, pore size and tortuosity, for samples made by the same fabrication technique might very well be correlated in certain relationships.