In this paper, we present low phase noise and low power of the voltage-controlled oscillators (VCOs) for 5 GHz applications. This chip is implemented by Taiwan Semiconductor Manufacturing Company (TSMC) standard 0.18 μm CMOS process. The designed circuit topology is included a current-reused configuration. It is adopted memory-reduced tail transistor technique. At the supply voltage 1.5 v, the measured output phase noise is-116.071 dBc/Hz at 1MHz offset frequency from the carrier frequency 5.2 GHz. The core power consumption is 3.7 mW, and tuning range of frequency is about 1.3 GHz from 4.8 to 6.1 GHz. The chip area is 826.19 × 647.83 um2.