A rapid and accurate method for the determination of cyromazine residues in vegetables by composite solid-phase extraction and reversed phase ion-pair liquid chromatography(IS-RPLC) was established. The target was extracted by multiple ultrasonic extraction with ammonium bicarbonate solution， purified by composite solid-phase extraction column， and separated and determined by IS-RPLC. The calibration curve showed good linearity in the range of 0.1~2 μg/mL with the correlation coefficient greater than 0.998， and the limit of detection (LOD) of the method reaches 0.012 mg/kg， which can meet the regulatory and judgment requirements for the residue of cyromazine. Recovery experiments show that the recovery range is 77.7%~87.0%， and the relative standard deviation (RSD) is 1.6%~3.7%. The problems of low extraction recovery and difficult purification in the determination of cyromazine were effectively solved. The chromatographic peak shape of cyromazine which separated by C8 column combining with the ion-pair reagent was sharp and anti-interference.