Porous ceramics green bodies of silicon carbide were formed by freeze-casting of silicon carbide/carbon black aqueous slurries in a mold where temperature distribution was controlled. The influence of solid loading on the pore structure of green bodies was investigated. Pore morphology of green bodies formed from slurries with various solid loading ranging from 25 to 50vol% experienced a gradual change. Appropriate solid loading of silicon carbide/carbon black slurry was concluded for fabrication of SiC ceramics with oriented pore structure. Two means were employed for changing ice crystallizing velocity, so that the influence of ice crystallizing velocity on pore size of green bodies was explored. It was concluded that pore size became larger under slow freezing condition, whereas smaller with the pre-cooling of silicon carbide/carbon black slurry.