This paper analyzes the frequency dependence of the gate transconductance (G m ) and output conductance (G d ) of a DTMOS in 0.25 μm PD SOI MOS technology. Our experimental results demonstrate for the first time that DTMOS devices suffer from a strong degradation of G m and G d around 1 GHz. An equivalent small-signal circuit is proposed to explain the observed phenomena. The model clearly identifies the non-zero value of the body contact resistance as the source of the G m and G d degradation. DTMOS stays a promising MOS structure for low power, low voltage high frequency applications.