To prepare a particle dispersion in which particles of a metal compound are dispersed in a dispersion medium containing an organic solvent as an essential component in a condition excellent in mono-dispersing property, and to obtain a composition of a coating agent containing the particle dispersion as an essential constitutional component.

The particle dispersion disperses the particles of the metal compound in the dispersion medium by using a dispersant, wherein the particle of the metal compound is at least one kind selected from the group consisting of a particle of a metal oxide, a particle of a metal (oxy)sulfide, a particle of a metal (oxy)selenide, a particle of a metal (oxy)nitride and a particle of a metal carbide, the dispersant comprises at least one kind selected from the group consisting of a hydrolysate condensate having degree of condensation of ≤20 obtained using a metal alkoxide and/or its partial hydrolysate and a metal alkoxide having a 4C or higher alkoxy group and/or an alkoxy alkoxy group, the dispersant requires an organic solvent as an essential component, and a compounding ratio of the dispersant is 0.5-10 wt.% based on the particle of the metal compound.