A thermal transfer image-receiving sheet comprising (1) a support comprising (a) a surface layer comprising a biaxially stretched film of a thermoplastic resin containing from 2 to 60% by weight of titanium dioxide fine powder and (b) a base layer comprising a biaxially stretched microporous film of a thermoplastic resin containing from 10 to 45% by weight of an inorganic fine powder and (2) an image-receiving layer provided on surface layer (a) of support (1), in which support (1) has a void volume of from 30 to 60% and a density of from 0.50 to 0.78 g/cm.sup.3, and surface layer (a) of support (1) has a center-line average roughness of not more than 0.5 .mu.m and a Bekk's smoothness of from 4,000 to 100,000 sec. The thermal transfer image-receiving sheet has an excellent cushioning effect due to the number of microvoids present in the support thereof and high sensitivity in a middle tone region owing to the titanium dioxide present in the surface layer of the support to provide a clear image having a high density even with reduced printing energy.