The aim of this study was to detect major whey proteins α-lactalbumin and β-lactoglobulin by reversed-phase high-performance liquid chromatography (RP-HPLC). RP-HPLC methods were developed using the column YMC Pack-C4, which enabled the separation of whey proteins within 30 min. Mobile phase was acetonitrile/water/0.1% trifluoroacetic acid (TFA) with gradient elution, flow rate was 1.0 mL·min−1, and the detection wavelength was 210 nm. Column temperature was 40 °C and injection volume was 20 μL. Milk samples contained α-lactalbumin and total β-lactoglobulin: No. 1 – 1500 mg·L−1 and 3600 mg·L−1; No. 2 – no α-lactalbumin and 450 mg·L−1 total β-lactoglobulin; No. 3 – 800 mg·L−1 and 94 mg·L−1, respectively.