A wide-range and low power consumption voltage-controlled oscillator according to the invention includes a logic control circuit, a parallel series controllable inverter bank and a voltage control load. The logic control circuit consists of a plurality of logic gates for receiving a selecting signal from an external device and then transmitting a control signal. The parallel series controllable inverter bank consists of a plurality of series controllable inverter banks electrically connected in parallel for receiving the control signal and outputting an oscillation signal, wherein the control signal is used to control the number of the series controllable inverter banks electrically connected in parallel. The voltage control load is electrically connected between the parallel series controllable inverter bank and ground for serving as a load of the parallel series controllable inverter bank.