A high-speed low power multi-phase clock generator with a simple duty-cycle correction circuit is presented. By adding tail transistors driven by the out-phase signal as a discharge path to correct the phase overlapping in the conventional design, 25% duty cycle multi-phase clocks are obtained with <1° phase error. Thanks to this simple topology, the proposed work is featured with fast-speed, low power with a small silicon area. Fabricated in a 0.13 µm RF CMOS process, the proposed clock generator has a measured operating frequency up to 2.73 GHz with a maximum power consumption of 2.5 mW from a 1.2 V supply.