A method of manufacturing a sintered body is provided. A molding powder, a gel-forming material powder and a solvent are mixed at a temperature not higher than a dissolving point of the gel-forming material. A treatment of pulverizing agglomerates containing the molding powder, gel-forming material powder and solvent absorbed in the gel-forming material powder is carried out. The mixture is then heated to a temperature not lower than the dissolving point thereby forming a sol. The sol is then cooled to a temperature not higher than the gel point, thereby forming a molding material. The molding material is used for producing a sintering body.