Antenna device for portable wireless terminal

An antenna device for a portable wireless terminal is provided. The antenna device includes a main antenna for mobile communication for transmitting and receiving signal in a first frequency band, a Transmit (Tx) sub-antenna for transmitting signals in a second frequency band, a Receive (Rx) sub-antenna for receiving signals in a third frequency band, and a controller for selectively using one of the Tx sub-antenna and the Rx sub-antenna if the second frequency band overlaps with the third frequency band, and for providing control such that the Tx sub-antenna and the Rx sub-antenna are simultaneously used if the second frequency band does not overlap with the third frequency band. Accordingly, without increasing the volume of the portable wireless terminal, an antenna space can be ensured and radiation performance can be improved.