[Objectives] To develop a method for the quantification of six human milk oligosaccharides (HMOs) in milk powder utilizing ion chromatography. [Methods] The sample was dissolved in water and deproteinized through acetonitrile precipitation, followed by freezing and centrifugation. The resulting supernatant was then diluted and filtered before being subjected to separation using a PA1 analytical column. The sample was analyzed using ion chromatography coupled with an amperometric detector and quantified by the external standard method. [Results] The limits of detection (LOD) for difucosyllactose (DFL), 2’-fucosyllactose (2’-FL), lacto-N-neotetraose (LNnT), lacto-N-tetraose (LNT), 3’-sialyllactose (3’-SL), and 6’-sialyllactose (6’-SL) were 8, 100, 15, 15, 10, and 6 mg/100 g, respectively. Correspondingly, the limits of quantification (LOQ) were 15, 300, 50, 50, 30, and 10 mg/100 g, respectively. The method exhibited excellent linearity over the concentration range of 2–20 μg/mL (R²> 0.999). Spiked recoveries ranged from 82.5% to 104.9%, with relative standard deviations (RSD) between 0.44% and 2.78%. [Conclusions] The method demonstrates excellent selectivity, precision, repeatability, and stability, thereby offering a reliable analytical method for quantifying six HMOs in milk powder.