A dual-band divide-by-2 quadrature injection-locked frequency divider (QILFD) is proposed to achieve high-speed, low power, wide-locking range, and accurate quadrature output phases. The QILFD consists of two dual-resonance differential voltage controlled oscillators and four coupling NMOS injectors in a ring configuration. The injectors are used as coupling devices of two differential ILFDs and are also used as common source amplifiers. The proposed QILFD has been implemented with the TSMC 90nm CMOS technology and the core power consumption is 2.31mW at the dc drain-source bias of 0.5V. At the input power of 0dBm, the low-band and high-band divide-by-2 operation ranges are respectively from 7.0GHz to 10.1GHz and 19.8GHz to 24.6GHz.