A fully integrated dual-band LC voltage control oscillator, designed in a 0.18um CMOS technology for 5.8 GHz/2.0 GHz wireless comminication applications, is described. The frequency band switching is accomplished with switched-inductor technique. The dual-band oscillator can be operated in 5.38-6.23 GHz and 1.78-2.07 GHz with 15% frequncy tuning range. Two different inductors are used for the frequency band switching. Frequency tuning is implemented by varying the capacitance of a MOS varactor. The measured phase noise is -109 dBc/Hz@1MHz and -112dBc/Hz@ 1MHz for frequency at 5.8GHz and 2GHz, respectively. This oscillator is fabricated in UMC's 0.18um one-poly-six-metal 1.8V process. The power dissipation of this dual-band VCO is 11.7 and 9.3 mW for oscillation frequency of 2GHz and 5.8GHz, respectively.