A user equipment apparatus for simultaneously transmitting signals from a plurality of wireless communication chips to which different wireless communication schemes are applied and a method for controlling a transmission power control of the user equipment apparatus are disclosed. The user equipment apparatus comprises a transmission mode decision module determining whether the user equipment apparatus is currently operated to transmit a signal through one wireless communication chip or simultaneously transmit signals, to which different wireless communication schemes are applied, through a plurality of wireless communication chips, and an intermodulation distortion (IMD) effect decision module determining whether a set of frequencies of the signals respectively transmitted from the plurality of wireless communication chips causes intermodulation distortion (IMD).