A seal-type thermal transfer image-receiving sheet comprising a release section and a seal section integrated, wherein the seal section is provided peelably from the release section, the seal section has a layered structure in which a pressure-adhesive layer and a receiving layer capable of receiving a sublimable dye are layered in the order mentioned from a side of the release section, and the seal section is not constituted only by the pressure-adhesive layer and the receiving layer but contains at least one other layer, said other layer containing a colorant, wherein when the seal section is peeled off from the release section, a black reference plate with a reflection density of 1.81 and the seal section peeled off are superposed together, and a reflection density of the black reference plate is measured from the side of the seal section, a value of the reflection density is 15% or more and 40% or less of the reflection density of the black reference plate alone, and when the black reference plate and the seal-type thermal transfer image-receiving sheet are superposed together and a reflection density of the black reference plate is measured from the side of the seal-type thermal transfer image-receiving sheet, the value of the reflection density is 15% or more and 40% or less of the reflection density of the black reference plate alone, wherein the release section includes a back face layer located on the outermost surface thereof on the side of the release section not in contact with the seal section, wherein a dynamic friction coefficient between surfaces of the release section not located on the side of the seal section is 0.24 or more, the dynamic friction coefficient being measured in compliance with JIS-P-8147, wherein the back face layer contains a thermoplastic resin and at least one of porous silica particles and nylon particles. the seal section is provided peelably from the release section, the seal section has a layered structure in which a pressure-adhesive layer and a receiving layer capable of receiving a sublimable dye are layered in the order mentioned from a side of the release section, and the seal section is not constituted only by the pressure-adhesive layer and the receiving layer but contains at least one other layer, said other layer containing a colorant, wherein when the seal section is peeled off from the release section, a black reference plate with a reflection density of 1.81 and the seal section peeled off are superposed together, and a reflection density of the black reference plate is measured from the side of the seal section, a value of the reflection density is 15% or more and 40% or less of the reflection density of the black reference plate alone, and when the black reference plate and the seal-type thermal transfer image-receiving sheet are superposed together and a reflection density of the black reference plate is measured from the side of the seal-type thermal transfer image-receiving sheet, the value of the reflection density is 15% or more and 40% or less of the reflection density of the black reference plate alone, wherein the release section includes a back face layer located on the outermost surface thereof on the side of the release section not in contact with the seal section, wherein a dynamic friction coefficient between surfaces of the release section not located on the side of the seal section is 0.24 or more, the dynamic friction coefficient being measured in compliance with JIS-P-8147, wherein the back face layer contains a thermoplastic resin and at least one of porous silica particles and nylon particles.