Abstract: In order to effectively characterize the RF noise characteristics in the strong inversion region of nanoscale MOSFET, the noise modeling method is studied. Based on the analysis of extracted results of radio frequency small-signal equivalent circuit parameters of 45 nm MOSFET, a compact model for the MOSFET's drain current noise is proposed. This model fully describes three kinds of main physical sources that determine the noise mechanism of 45 nm MOSFET, including intrinsic drain current noise, thermal noise induced by the gate parasitic resistance, and coupling thermal noise induced by substrate parasitic effect. The accuracy of the proposed model is verified by noise measurements, and the intrinsic drain current noise of 45 nm MOSFET is proved to be the suppressed shot noise, and with the decrease of the gate voltage, the suppressed degree gradually decreases until it vanishes.