The invention discloses a noise suppression circuit and a noise suppression method for a frequency modulator. The frequency modulator with the noise suppression circuit comprises a tuning circuit, a frequency conversion circuit, an intermediate-frequency amplification circuit, the noise suppression circuit, a detecting circuit, an audio pre-amplification circuit and an audio power amplification circuit, wherein the tuning circuit is used for selecting a signal of certain frequency; the frequency conversion circuit mixes the signal selected by the tuning circuit and a local oscillator to obtain an intermediate-frequency signal; the intermediate-frequency amplification circuit amplifies the intermediate-frequency signal obtained by the frequency conversion circuit to meet the requirements of the detecting circuit; the noise suppression circuit suppresses noise produced when the frequency-modulated signal is not received; the detecting circuit demodulates an audio signal from an audio packet, and filters a high-frequency signal; the audio pre-amplification circuit performs open loop pre-amplification on the audio signal output by the detecting circuit; and the audio power amplification circuit performs closed loop amplification on the audio signal to drive a loudspeaker. By the circuit and the method, the noise produced when the frequency-modulated signal is not received can be effectively suppressed.