One of the fuel cells, the molten carbonate fuel cell (MCFC), comes into prominence due to its high energy potential and suitability for industrial applications. Nickel porous structures are used as anodes and cathodes for MCFC. In this study; Green sheets were obtained by means of tape casting method performing on the prepared mixtures. 23% - 37% by weight nickel oxide was used in the mixture for the purpose of synthesizing cathode green sheets. Different slurry were prepared using different ratios of polyethylene glycol (PEG) as plasticizer, polyvinyl butyral (PVB) as binder, glycerol as dispersant and butanol with hexanol as a solvent. The optimum mixture formulation for the tape casting has been determined by measuring, tensile strength on the green tape. Tensile elongation of green tape refers to resistance to dissolution, cracking and breakage for the green tape slurry. Tensile force parameters were evaluated for the green tape's slurries. Maximum tensile force and thickness of the green tape is critical factor in order to choose the optimum mixture formulation of cathode slurries. Optimum composition was determined as 23% nickel oxide, 3% binder and 3% plasticizer according to analyze two level experimental factorial design and response surface optimization technique.