In this paper, a fully integrated Ku-band voltage controlled oscillator (VCO) with low phase noise is presented in a GaAs heterojunction bipolar transistor (HBT) technology. A cross-coupled configuration is employed to achieve low phase noise, and to achieve high output power, the largest HBT and higher bias current are adopted. The implemented VCO demonstrates that the oscillation frequency is from 13.77[Formula: see text]GHz to 14.8[Formula: see text]GHz, with a maximum 4.83[Formula: see text]dBm output power at 13.77[Formula: see text]GHz. The phase noise of the VCO is [Formula: see text]100.2[Formula: see text]dBc/Hz at 1[Formula: see text]MHz offset from 14.36[Formula: see text]GHz oscillation frequency. The VCO consumes 61.2[Formula: see text]mW from 6[Formula: see text]V supply and occupies an area of 0.51[Formula: see text]mm[Formula: see text][Formula: see text]mm. Finally, the figure-of-merits (FOMs) for VCOs are discussed.