The invention discloses a digital control single-stage multi-clock phase interpolator with a stable duty cycle. The phase interpolator has input clock signals CKI and CKQ, comprises a digital controlselection unit, a digital phase interpolation unit and a data selector, and is mainly used in various high-speed clock data recovery acquisition systems to provide an accurate multi-phase clock in thesystems for the systems to select the optimal sampling clock phase. The digital control single-stage multi-clock phase interpolator with a stable duty cycle has a simple requirement for input, requires only two digital input high-low level signals with a phase difference, has a simple internal sequential control logic circuit, and can output a high-precision multi-phase clock with a constant dutycycle.