To establish a method for the determination of chromium form Cr (Ⅲ) and Cr (Ⅵ) simultaneously in gelatin capsule.MethodsChromium in gelatin capsule was ultrasonic extracted and determined using reversed-phase ion-pair chromatography with inductively coupled plasma mass spectrometry (RPIC/ICP-MS). ResultsCr (Ⅲ) and Cr (Ⅵ) were not interchangeable in the process of ultrasonic extraction and analysis, and only Cr (Ⅵ) could be determined. When extracted by EDTA, both Cr (Ⅲ) and Cr (Ⅵ) could be measured. Because of the interconversion between Cr (Ⅲ) and Cr (Ⅵ), the total chromium could be calculated accordding to peak area. The amount of Cr (Ⅲ) could be determined by subtracting Cr (Ⅵ) from the total chromium. The detection limit of Cr (Ⅲ) and Cr (Ⅵ) were 0.67 and 0.51 mg/kg, and the linear range was 5-100 μg/L.ConclusionThis method could be used to determine the chromium form in gelatin capsule.