Fourteen Chinese traditional medicines were digested by microwave digestion, which are generally applied to treat tumor in clinic, and the contents of U, Th and Tl in the fourteen Chinese traditional medicines were determined by inductively coupled plasma mass spectrometry (ICP-MS), and the results show that the change ranges of the elements contents were: 0.005 153-0.1534 microg x g(-1) for U; 0.03501-0.4628 microg x g(-1) for Th; 0.00143-1.600 microg x g(-1) for Tl. The contents of U, Th and Tl in the fourteen Chinese traditional medicines were low, and not with one accord. The determination results of the fourteen Chinese traditional medicines were analyzed by SPSS 11.5, and the results show that there were not significant deviations(p>0.05) of the contents of U, Th and Tl between the medicine of treating the toxifying disease with poisonous agents and the medicines of heat-clearing. The study indicates that inductively coupled plasma mass spectrometry (ICP-MS) is a quick, accurate, sensitive method to determine the contents of U, Th and Tl in Chinese traditional medicine, and the results of this study provide reference data for using Chinese traditional medicine safely in clinic and developing Chinese traditional medicine.