A fully integrated nanoelectromechanical system (NEMS) resonator together with a compact built-in complementary metal-oxide-semiconductor (CMOS) interfacing circuitry is presented. The proposed low-power second generation current conveyor circuit allows measuring the mechanical frequency response of the nanocantilever structure in the megahertz range. Detailed experimental results at different DC biasing conditions and pressure levels are presented for a real mixed electromechanical system integrated through a combination of in-house standard CMOS technology and nanodevice post-processing based on nanostencil lithography. The proposed readout circuit can be adapted to operate the nanocantilever in closed loop as a stand-alone oscillator.