This invention relates to a compact electro-acoustic transducer (10) to be used in the ear hole which prevents oppressive and inharmonious sensations to the auricle (A) when used and also prevents the deterioration of the reproduced sound quality. To do this, according to this invention, the electro-acoustic transducer (10) is formed of an outer casing (30) which houses therein an electro-acoustic transducer element (20), is shaped in size to be engagable with the concave portion of the auricle (A) and supported at least two points by one part of the auricle (A) when engaged with the concave portion of the auricle (A) and of a cord supporting member (50) extended from the outer casing (30) to be contact with the outer surface of the auricle (A) at a lower position than the respective supportion positions of the outer casing (30).