A heating tool (50) is provided with a mask main body (51) covering both eyes, a heating element (100) provided to the mask main body (51), and a pair of ear hooks (52L, 52R) that are joined respectively to both longitudinal ends of the mask main body (51) and hold the mask main body (51) so as to cover both eyes of the wearer, the heating tool (50) fulfilling the following conditions. (Conditions) (i) The ear hooks (52) have holes (54) for hooking over the ear, and the relationship (La × 2 + Lb) <； 285 is satisfied, where La (mm) is the maximum length of the hole (54), and Lb (mm) is the length from the end portion on the mask-main-body (51) side at La (mm) of one hole (54) to the end portion on the mask-main-body (51) side at La (mm) of the other hole (54)； (ii) the stress (N) when the mask main body (51) is extended 4 cm in the longitudinal direction is less than 70 N； and (iii) the change in stress in the La direction of the ear hooks (52), represented by formula (1), is 35% or higher. Formula (1): Change in stress (%) = {[stress at 100% extension (N)] – [stress at 10% return extension (N)]/stress at 100% extension (N)} x 100L'invention concerne un outil de chauffage (50) pourvu d'un corps principal de masque (51) recouvrant les deux yeux, d'un élément chauffant (100) disposé sur le corps principal de masque (51) et d'une paire de crochets d'oreille (52L, 52R) qui sont reliés respectivement aux deux extrémités longitudinales du corps principal de masque (51) et maintiennent le corps principal de masque (51) de façon à recouvrir les deux yeux de l'utilisateur, l'outil de chauffage (50) remplissant les conditions suivantes. (Conditions) (i) Les crochets d'oreille (52) comprennent des trous (54) pour s'accrocher à l'oreille, et la relation (La × 2 + Lb) <； 285 est satisfaite, La (mm) représentant la longueur maximale du trou (54) et Lb (mm) correspondant à la longueur depuis la partie d'extrémité sur le côté corps principal de masque (51) au niveau de La (mm) d
