Abstract: Six harmful metal elements, including Pb, As, Hg, Cd, Cr and Cu in tremella before and after sulphur fuming, which was simulated in laboratory, were analysised by coupled plasma mass spectrometry ( ICP-MS) after microwave digestion.The results showed that sulphur fumed tremella had an notable raise in arsenic content with mercury content increased as well, and did not changed significantly in the other 4 metals as the amount fuming time increased.As a food processing method, the influence of sulphur fuming on food quality and safety should be reserved for further consideration.