Abstract: Hydrophilic interaction chromatography(HILIC),combining polar organic-aqueous mobile phase with a hydrophilic stationary phase,has been shown to be a powerful tool for separating polar analytes which have poor retention on traditional reversed-phase liquid chromatography(RPLC). HILIC-tandem mass spectrometry (HILIC-MS/MS) has attracted growing interest in the quantitation of analytes from complex biological matrices. This article briefly reviews the concept and mechanism of HILIC system,and its recent applications in quantitative bioanalysis.