A heat radiation shielding component dispersion contains fine hexaboride particles and a polymer type dispersant in which the fine hexaboride particles are dispersed. The polymer type dispersant is mixed in the fine hexaboride particles in a proportion of from 0.3 part by weight or more to less than 50 parts by weight based on 1 part by weight of the fine hexaboride particles, and the dispersion does substantially not contain any organic solvent. A process for preparing the heat radiation shielding component dispersion is characterized by adding the polymer type dispersant to a dispersion in which fine hexaboride particles have been dispersed in an organic solvent, in a mixing proportion of from 0.3 part by weight or more to less than 50 parts by weight based on 1 part by weight of the fine hexaboride particles, and thereafter removing the organic solvent.