This article proposes excellent class-C voltage-controlled oscillator (VCO) with dual-balanced mixer. The oscillator consists of a double resonance LC resonator in shunt with one pair of capacitive cross-coupled nMOSFETs. The common source of cross-coupled nMOSFETs is congregated to the ground from a tail transistor in shunt with a capacitor, dynamic bias is applied to the gate of the tail. The proposed oscillator has been implemented with the tsmc $0.18\mu\mathrm{m}$ CMOS technology and the core current of 2.535 mA and DC dissipation of 2.99 mW respectively at the dc drain-source bias of 1.18V. The oscillator can generate differential high-band and low-band signals at 4.286GHz and 2.94GHz respectively. The die area of the class-C oscillator is $1.87\times 1.109\ \text{mm}^{2}$. The layout dimension of the mixer is $0.6\times 0.7\ \text{mm}^{2}$.