Abstract: The present invention provides: an inorganic layered compound dispersion prepared by cleaving the inorganic layered compound to a thinner layer level and capable of providing high corrosion resistance and gas barrier properties when utilized in the form of a coating composition or a gas barrier coating composition; a gas barrier coating composition with which films having high transparency and satisfactory gas barrier properties can be obtained at low cost when the gas barrier layers are formed ina thinner film form and, when the filmthickness is increased, films having good transparency and still better gas barrier properties can be obtained; and plastic- or paper-based gas barrier packaging containers having high gas barrier performance characteristics as obtainable by application of such a gas barrier coating composition. The present invention provides: an inorganic layered compound dispersion, wherein an inorganic layered compound (b) is dispersed using a peroxide (a) in a dispersion medium.