Abstract: A method for the determination of 7 ethanolamine compounds including dimethylamine, diethylamine, ethanolamine, diethanolamine, triethanolamine, dimethylethanolamine and diethyl ethanolamine in cosmetics by high performance liquid chromatography-tandem mass spectrometry was proposed. The sample was extracted by the mixed solution composed of 0.005 mol·L^-1 ammonium acetate solution and acetonitrile at volume ratio of 1∶9. After filtration, the filtrate was injected into a high performance liquid chromatography-tandem mass spectrometer. Gradient elution was performed on Agilent InfinityLab Poroshell 120 HILIC-Z column (100 mm×2.1 mm, 2.7 μm) as stationary phase, with the mixed solutions composed of 0.005 mol·L^-1 ammonium acetate solution and acetonitrile at different volume ratios as mobile phase. The 7 separated targets were scanned by electrospray ion source with positive ion mode, and detected by dynamic multi-reaction monitoring mode. It was shown that linear relationships between the mass concentrations and peak areas of quantitative ions for 7 ethanolamine compounds were kept in definite ranges, with detection limits (3S/N) in the range of 0.09-5.39 ng·g^-1. Test for recovery was made on the three kinds of negative samples including water base, milk base and cream base by standard addition method, giving results in the range of 88.0%-115%,with RSDs (n=6) of the determined values were less than 6.0%. The method was applied to analysis of 20 batches of cosmetics, among which targets were not detected in 17 batches of cosmetics, and triethanolamine was detected in 3 batches of cosmetics, with mass fractions in the range of 0.17%-1.0%.