An earpiece including a tubular core portion attached to an end of an electro-acoustic transducer and extending in an acoustic wave output direction, and an external auditory canal fitting portion disposed outside the core portion to cover an end surface of the core portion and having lower hardness than the core portion is provided. This maintains appropriate flexibility of the external auditory canal fitting portion covering the end surface of the core portion and forms the core portion with appropriate hardness. This eliminates sound quality degradation due to the core portion deformation, earpiece detachment and contact of the core portion with the external auditory canal. Consequently, this improves fitting properties with the external auditory canal and attachment properties with the electro-acoustic transducer. The earpiece which improves fitting properties with the external auditory canal and attachment properties with the electro-acoustic transducer, and the electro-acoustic transducer including the same are thereby provided.