Abstract: This paper presents a high performance Operational Transconductance Amplifier (OTA) that combines two linearization techniques, and one gain enhancement technique. The two linearization technique are adaptive biasing of differential pairs and resistive source degeneration. The gain enhancement technique is Comman mode feedback Amplifier. The Operational Transconductance Amplifier has ±0.9v power supply. Operational Transconductance Amplifier has been simulated with TANNER 0.18μm CMOS technology in Tspice. The simulated third order harmonic distortion (HD3) with applying a 300mvP-P differential input, remains below -60dB at 3MHz frequency, also the simulation result gives Transconductance gain(gm) 5.247mA/V for 10mV(p-p) input voltage.