A wideband front-end device comprises a wideband amplifying module and a plurality of narrow band filters. The wideband amplifying module comprises an input end, a plurality connecting ends and at least one receiving end. A wideband transmitting RF signal can be transmitted to one of the connecting ends from the input end according to the frequency band thereof. Thus, the wideband transmitting RF signal can be divided into several narrow band signals with different frequency bands. Each narrow band signal with different frequency bands is transmitted to different connecting ends and narrow band filters respectively. Therefore, each narrow band filter can be used to filter wideband transmitting RF signal or narrow band signals with different frequency bands respectively to reduce production costs of the wideband front-end device.