To provide a headrest device which has a resin cover 3 formed separately from a metal plate 2 and a metal stay 1, prevents generation of abnormal noise without using a shock absorbing material and prevents backlash.

The first split member 4 of a core member 3 is integrally formed with a fixing means which engages and fixes a flat plate part 21 of a metal plate 2 mechanically with the first split member 4, the flat plate part 21 is tightly fixed to the first split member 4, then, the first split member 4 alone can absorb stress.