To provide a thermal label in which a color development state in a thermal coloring layer is maintained well for a long period of time.

In the thermal label 1 comprising a thermal coloring layer 3 which develops colors by applying heat on the surface side of a paper material 2 and an adhesive layer 4 containing plasticizer at the back side of the paper material 2, a penetration blocking layer 5 for blocking penetration of the plasticizer is provided between the thermal coloring layer 3 and the adhesive layer 4. Thereby, since the penetrating path of the plasticizer oozed from the adhesive layer 4 is blocked, the plasticizer does not penetrate to the thermal coloring layer 3 and even when the thermal label 1 in a sticking state to the object to be stuck is stored for a long period of time, the decolorization phenomenon of a developed color printed section of the thermal coloring layer 3 resulting from contact to the plasticizer does not occur and the color development state in the thermal coloring layer 3 is maintained well for a long period of time.