PURPOSE: A slim hearing aid is provided to obtain balanced structure by mutually connecting a main body and a sub body with a connection tube. CONSTITUTION: A hearing aid main body(110) comprises a receiver for receiving an external sound and an amplifier for amplifying the received external sound. One side of a connection tube(120) is connected to one side of the upper side of the main body. The connection tube includes an internal wire. The other side of the connection tube is connected to a hearing aid sub body(130). The receiver is installed inside the hearing aid sub body. The receiver converts an electric signal from the amplifier of the main body into a sound signal. A connection unit for connecting an earpiece is formed on one side of the hearing aid sub body. The earpiece is an insertion structure like an earmold or eartip(154) mounted on the ear. The earpiece is connected to one side of a flexible tube(152). The flexible tube is mounted on the connection unit.
