Summary: This paper presents a novel wide tuning range CMOS Voltage Controlled Oscillator (VCO). VCO uses an on-chip variable inductor as an additional variable element to extend the tuning range of VCO. The fabricated variable inductor achieves the variable range of 35%. The VCO was fabricated using 0.35 µm standard CMOS process, and can be tuned continuously from 2.13 GHz to 3.28 GHz (tuning range of 38%) without degradation of phase noise. Wide tunable LC-VCO using a variable inductor is one of the key circuits for reconfigurable RF circuit.