A front face side substrate provided between a supporting member and a receiving layer of a thermal transfer image-receiving sheet. The front face side substrate includes a front face side layer provided on one surface of a substrate layer and a rear face side layer provided on another surface of the substrate layer. The substrate layer includes (A) a propylene-based polymer, (B) calcium carbonate, and (C) titanium oxide, and the weight of (A) is 70% by weight to 94.5% by weight, the weight of (B) is 5% by weight to 28% by weight, and the weight of (C) is 0.5% by weight to 3% by weight, based on the assumption that the total weight of (A), (B) and (C) is 100% by weight. The front face side layer includes a modified propylene-based polymer, and the rear face side layer includes a propylene-based polymer.