A 60-GHz high quadrature accuracy low dc power quadrature voltage-controlled oscillator (QVCO) using self-injection coupling (SIC) is proposed and demonstrated in 90 nm CMOS technology. By using SIC technique, this QVCO achieves low phase noise and good quadrature accuracy. Moreover, the amplitude/phase errors of the QVCO are fully characterized via a four-port vector network analyzer. The proposed 60-GHz QVCO exhibits a phase noise of -95 dBc/Hz at 1-MHz offset frequency, an amplitude error of 0.12 dB, and a phase errors of 1.2°. The dc power consumption is 13.3 mW with a supply voltage of 0.7 V. The chip size of the proposed QVCO is 0.75×0.6 mm2. This work has the lowest dc power consumption and the best figure-of-merits with high quadrature accuracy among the all reported millimeter-wave CMOS QVCOs.