A surface-coated cutting tool comprising: a substrate composed of cemented carbide; and a coating film formed on the substrate, the coating film including an intermediate layer in contact with the substrate and an upper layer formed on the intermediate layer, the upper layer being made up of a single layer consisting of an upper base layer which is a layer in contact with the intermediate layer or multiple layers constituted of two or more layers including the upper base layer, the substrate having a hexagonal crystal system, the intermediate layer and the upper base layer having an NaCl crystal structure, the intermediate layer having a thickness not smaller than 3 nm and not greater than 10 nm, a mismatch in lattice interplanar spacing in an interface region between the substrate and the intermediate layer being not higher than 65% of a theoretical value of a mismatch in lattice interplanar spacing between the substrate and the upper base layer, and a mismatch in lattice interplanar spacing in an interface region between the intermediate layer and the upper base layer being not higher than 65% of the theoretical value of the mismatch in lattice interplanar spacing between the substrate and the upper base layer, wherein the intermediate layer contains a carbide, a nitride, or a carbonitride containing at least one element selected from the group consisting of elements forming the upper base layer and at least one element selected from the group consisting of elements forming the substrate, and wherein the upper layer contains one or more elements selected from group IV elements, group V elements, and group VI elements in the periodic table and Si and Al and one or more elements selected from C, N, and O, and wherein a theoretical value of mismatch in lattice interplanar spacing (%) between the substrate and the upper base layer is expressed as the formula: a theoretical value of mismatch in lattice interplanar spacing % between the substrate and the upper base layer = 100 × a lattice interplanar spacing in the upper base layer − a lattice interplanar spacing in the substrate / a lattice interplanar spacing in the substrate wherein the theoretical value is expressed as an absolute value, the lattice interplanar spacing in the upper base layer is measured using the method described in the description and the lattice interplanar spacing in the substrate is measured using the method described in the description. a substrate composed of cemented carbide; and a coating film formed on the substrate, the coating film including an intermediate layer in contact with the substrate and an upper layer formed on the intermediate layer, the upper layer being made up of a single layer consisting of an upper base layer which is a layer in contact with the intermediate layer or multiple layers constituted of two or more layers including the upper base layer, the substrate having a hexagonal crystal system, the intermediate layer and the upper base layer having an NaCl crystal structure, the intermediate layer having a thickness not smaller than 3 nm and not greater than 10 nm, a mismatch in lattice interplanar spacing in an interface region between the substrate and the intermediate layer being not higher than 65% of a theoretical value of a mismatch in lattice interplanar spacing between the substrate and the upper base layer, and a mismatch in lattice interplanar spacing in an interface region between the intermediate layer and the upper base layer being not higher than 65% of the theoretical value of the mismatch in lattice interplanar spacing between the substrate and the upper base layer, wherein the intermediate layer contains a carbide, a nitride, or a carbonitride containing at least one element selected from the group consisting of elements forming the upper base layer and at least one element selected from the group consisting of elements forming the substrate, and wherein the upper layer contains one or more elements selected from group IV elements, group V elements, and group VI elements in the periodic table and Si and Al and one or more elements selected from C, N, and O, and wherein a theoretical value of mismatch in lattice interplanar spacing (%) between the substrate and the upper base layer is expressed as the formula: a theoretical value of mismatch in lattice interplanar spacing % between the substrate and the upper base layer = 100 × a lattice interplanar spacing in the upper base layer − a lattice interplanar spacing in the substrate / a lattice interplanar spacing in the substrate wherein the theoretical value is expressed as an absolute value, the lattice interplanar spacing in the upper base layer is measured using the method described in the description and the lattice interplanar spacing in the substrate is measured using the method described in the description.