A thermal head has a head substrate including exothermic bodies which generate heat when electricity is supplied thereto, a common electrode connected with first ends of the exothermic bodies, and independent electrodes connected with second ends of the exothermic bodies. A printed circuit board (PCB) includes driving elements controlling the electricity supplied to the exothermic bodies. The head substrate and PCB are attached on a heat sink such that an end surface of the head substrate adjoins an end surface of the PCB. The independent electrodes are wire-connected with the corresponding driving elements across a gap between the adjoining end surfaces to define a wire-connection unit, which is sealed with resin. An adhesive layer is partially disposed between the PCB and the heat sink such that a space is provided therebetween. The space communicates with the outside of the thermal head and with the gap.