There is prepared in inorganic composite containing a needle-like inorganic material or a fiber-like inorganic material which is present as a mixture in isotropic solid vitreous inorganic material while maintaining its needle-like or fiber-like structure. The inorganic composite is prepared by a process comprising the steps ofkneading a mixture containing a vitreous inorganic material and a needle-like or fiber-like inorganic material which does not melt at the softening point of the vitreous material;molding the mixture into a predetermined shape; andcalcining the molded mixture at a temperature higher than the softening point of the vitreous inorganic material and below the melting point of said needle-like or fiber-like inorganic material.