Abstract: Flat ceramic body prepared by gel-casting is prone to warping while in the process of drying, which severely restricts the application of this technology in the field of ceramic molding.In this article, SnO₂ powder is used to prepare slurry of high solid content and low viscosity and the introduction of the curing agent is also changed in the process of gel-casting.In this way, the flat green body of large size without warping is prepared successfully.