This paper presents a wide band RF MEMS VCO operating at 10 GHz. The designed VCO is based on high performances RF MEMS solenoid inductor. We have used HFSS software for design and analysis of different RF MEMS solenoid inductors. Best performances are obtained using SU8 dielectric substrate and copper coil: Qmax= 60.9, L = 2.6 nH at 10 GHz, and SRF= 20.8 GHz. Moreover, we have investigated the time domain and the frequency responses of our RF MEMS VCO. The obtained results show symmetrical sinusoid signals with high voltage outputs upper than 1.2 V and a low phase-noise PN =-102.37 dBc/Hz at 1 MHz. In addition, the frequency band is comprised between 10.09 GHz and 14.6 GHz leading to a wide tuning range of TR=44.69%.