Abstract:A method was established for the determination of Arsenious Acid(As(Ⅲ)）and Arsenic Acid（As(Ⅴ)）in Anti-prickly heat powder and Body powder by High Performance Liquid Chromatography Inductively Coupled Plasma Mass Spectrometry(HPLC-ICP-MS), the method was used to detect the levels of As(Ⅲ) and As(Ⅴ) in Anti-prickly heat powder and Body powder sample which purchased from various markets. The sample was extracted by heat extraction method, the extracted liquid was separated by HAMILTON PRP-X100（250 mm×4.1mm,10μm）column using 150mM ammonium corbonate solution with 2% methanol as the mobile phase for isocratic elution, then determined by inductively coupled plasma mass spectrometry. The calibration curves of As(Ⅲ)and As(Ⅴ)in the range of 1.0~50.0ng/ml showed a good linearity, the correlation coefficients were all no less than 0.9990. The limits of detection（3S/N）for As(Ⅲ) and As(Ⅴ) were 0.0015mg/kg and 0.0011mg/kg respectively. The spiked recoveries of As(Ⅲ) and As(Ⅴ) were in the rang of 90.2%~95.9%、103.4%~107.7%, with relative standard deviations(RSD) were in the rang of 2.1%~4.6%、2.7%~5.2%, respectively. This method was proved to be simple, rapid, sensitive and effective for determining As(Ⅲ) and As(Ⅴ) in Anti-prickly heat powder and Body powder. Among 34 samples from 20 brands, the detection rate was 67.6%, and the contents of As(Ⅲ) and As(Ⅴ) in the detected samples ranged from 0.0065 to 0.0148mg/kg and 0.0061 to 0.1051mg/kg, respectively. The average values of As(Ⅲ) and As(Ⅴ)in the detected samples were 0.0098 mg/kg and 0.0229 mg/kg, respectively.