In this paper, an oscillator based on a Vibrating Body Field Effect Transistor (VB-FET) working at 9.4MHz is presented. The electrical characteristics of this active MEM resonator are detailed for static and dynamic operation. The benefit of the intrinsic gain for oscillator design is analyzed and an oscillator design is proposed based on these findings. The reported oscillator performance shows the advantages of an active MEM resonator for the construction of MEM based oscillators with respect to the reduced requirements on the electronics. © 2009 by Department of Microelectronics & Computer Science.