Abstract: Using microwave digestion combined with inductively coupled plasma mass spectrometry ( ICP-MS) , the change of17 metal elements including Na, K, As, Pb, Cd, Sn, Ti, Mg, Fe, Cu, Mn, Zn, Ca, Al, Ni, Cr and Ba were measured in the medium-temperature Daqu starter over the manufacturing process. With the employment of SPSS software, statistical analysis of the difference of related metal elements in the Daqu surface and Daqu core was applied using t-test.The results suggested that the overall content of metal elements during the fermentation varied slightly, and showed no clear correlation with starter fermentation time.The amount of Cu and Fe in the center of starter significantly decreased upon increasing fermentation time, which was reversed comparing with those in the out-layer starter. In the meantime, Zn concentration increased in the starter center but declined in the out-layer. The time-dependent concentration change of Cu, Fe and Zn might be linked to the preferential distribution of aerobic and anaerobic microbes in the starter.