A hearing aid (100) comprises a body case (2) that is worn behind an ear (1), a sound conductor (3) that is linked at one end to the body case (2) and is linked at the other end to an earpiece (6), and an engaging component (8) for holding the earpiece linked to the other end of the sound conductor in the external auditory canal (7) of the ear (1). The engaging component (8) is made up of a first arc part (8a) disposed on the earpiece (6) side, a second arc part (8b) that is larger than the first arc part (8a) and is disposed opposite the first arc part (8a), a first linking part (8c) that links one end of the first arc part (8a) and one end of the second arc part (8b), and a second linking part (8d) that links the other end of the first arc part (8a) and the other end of the second arc part (8b). The second linking part (8d) has a shape such that its center part protrudes toward the first linking part (8c). This constitution allows the hearing aid (100) to be put on more easily.