This paper describes design considerations and characteristics of oscillator circuitry for electrostatically driven silicon-based one-port resonators, used as resonant strain gauges. The oscillation conditions for a general, single transconductance oscillator are theoretically derived. In order to start oscillation, guidelines to select proper bias conditions for the resonator are presented, taking the non-linear effects into account. An oscillator circuit has been designed in CMOS technology in order to verify the theory experimentally. Experimental results of the oscillator in combination with a silicon beam resonator are given.