This paper presents small-signal and noise modeling for radio-frequency (RF) silicon-on-insulator (SOI) dynamic threshold voltage (DT) metal-oxide-semiconductor field-effect transistors (MOSFETs). The inherent body parasitics, such as source- and drain-side junction capacitances, and access body resistance have been incorporated in this model. In addition, the analytical equations useful for parameter extractions are derived. The modeling results show good agreements with the measured data both in RF small-signal and noise aspects up to 12 GHz. Besides, we have made comparisons of important model parameters for DT and standard MOSFETs. The extracted parameters show reasonable trend with respect to applying voltages and channel lengths, which reveals the accuracy of the extraction results using our proposed method.