The invention provides a wireless communication device working in a first radio frequency mode and a second radio frequency mode so as to receive and transmit a first-kind radio-frequency signal and a second-kind radio-frequency signal respectively, and the first-kind radio-frequency signal and the second-kind radio-frequency signal are basically the same in frequency. The wireless communication device comprises a controller, a first switch, a power amplifier and a second switch. The controller is used for transmitting a first voltage control signal to the power amplifier in the first radio frequency mode and transmitting a second voltage control signal to the power amplifier in the second radio frequency mode. The first switch is used for transmitting the first-kind radio-frequency signal and the second-kind radio-frequency signal to the power amplifier. The power amplifier is used for amplifying the first-kind radio-frequency signal according to the first voltage control signal and amplifying the second-kind radio-frequency signal according to the second voltage control signal. The power amplifier is further used for transmitting the amplified first-kind radio-frequency signal and the amplified second-kind radio-frequency signal to the second switch. By means of the wireless communication device, the design cost is reduced effectively.