In this study, the effect of particle shape on the filtration rate and shear strength of the mineral filter cakes was investigated. Shear strength of the mineral filter cakes is dependent on the particle shape, size and surface tension as well as the applied pressure and saturation degree. One of the most effecting parameter of the shear strength of the mineral filter cakes is the particle size and shape. The x-ray diffractometer results showed that dolomite is rhombohedral and quartz is hexagonal. Also, the surface analysis of the two minerals by multipoint BET analysis showed that the surface area and pore volume of quartz are about two times higher than that of dolomite. The laboratory experiments showed that the filtration rate of quartz is greater about two times than that of dolomite. Although the two minerals have the same particle size, i.e. 15 mum, the shear strength of quartz is higher about 1.5- 2 times than that of dolomite at the same conditions again. These results clearly show that the shape factor of mineral (the mineral type) has a determining parameter on the filtration rate and the shear strength of the mineral filter cakes.