A hair dryer includes a main body, a handle, and a diffuser. The diffuser includes a diffusing case. The main body is provided such that a front end of an outer wall surrounds the gas outlet, a first coupling portion coupled with the diffuser is provided at the front end, and the diffusing case includes a second coupling portion coupled to the first coupling portion while surrounding a gas inlet hole defined at a rear side. The first coupling portion includes a wireless power transmitter to wirelessly supply power to the diffuser, and the second coupling portion includes a wireless power receiver to wirelessly receive the power from the wireless power transmitter.