The properties of green sheet were investigated in order to understanding an effects of organic solvent mixture ratio for solid oxide fuel cells fabrication. The purpose of this work is to optimize the slurry condition using the design of experiment to improve green sheet properties. The elongation increased with increasing amount of binder and solvent. With increasing amount of solvent, the air permeability increased but the tensile strength decreased. The best properties of the green sheet appeared amount of the binder 17 wt%, solvent 35 wt% and powder 48 wt%. The optimum condition of green and sintered density for solid oxide fuel cells fabrication was obtained in the sample pressured at 800 $kgf/cm^2$.