PURPOSE: To keep head cool in sports and work by installing a thermoelectric cooling element having Peltier effect on a cap, setting the heat absorbing part inside.

CONSTITUTION: A reflection layer 3 is formed on the surface of the top cover part 2 of cap 1, and a thermoelectric cooling element 4 having Peltier effect is installed in a fitting hole 2A on the top of the top cover part 2. In the thermoelectric cooling element 4, N-type elements 4A and P-type elements 4B are arranged in parallel, and one edge part is connection-fixed integrally with a heat absorbing plate 4C, and heat generating plates 4D and 4D are fixed at the other edge part, and a cord 6 connected with a power source 5 is connected with the heat generating plate 4D on the N-type element side. A protecting plate 7 serving as heat radiation body is installed on the heat generating plates 4D and 4D, and a heat exchange body 8 which serves as protection is installed under the heat absorbing plate 4C. Thus, the heating value necessary for the heat generation of the heat generating plates 4D and 4D is absorbed from the heat absorbing body 4C, and the heat of the heat exchange body 8 is absorbed, and the temperature of the air in the cap 1 is lowered to develop the cooling action.