The present invention discloses a radio frequency applying circuit which uses the switch group that is composed of two bipolar junction transistors working in the reverse active area for replacing theN channel metal-oxide-semiconductor transistor used in the existing technique, and then the circuit is used for realizing the function of the oscillator or the band-pass amplifier according to the circuit character of the active circuit. Thereby the switch group is facilitated not only can obtain the efficacy which can be obtained by the existing NMOS transistor, but also the size dimension of the component, the conducting resistance value in conducting, the stray capacitance value in closing and the power consumption of the radio frequency applying circuit using the switch group can be reduced, and thereby increasing the resolving capability of the capacitor unit of the inductance capacitance resonance circuit and increasing the efficacy of the radio frequency applying circuit using theswitch group.