In order to achieve the above-mentioned object or another objective, a portable acoustic device according to one aspect of the present invention comprises: a man body housing having an opening at a first surface thereof; an acoustic output unit provided inside the main body housing; an ear housing having a first end portion connected to the opening at the first surface of the main body housing, and having an acoustic hole formed at a second end portion; and a rotating module for rotating the ear housing relative to the main body housing, wherein the portable acoustic device can be carried by being inserted into the ear of a user, can be worn in either the left ear or the right, and increases wearing sensation by being wearable since the angle thereof is changed to be suitable for the ears of the user.