Abstract: An analytical method using inductively coupled plasma mass spectrometry (ICP-MS) coupled with microwave digestion for simultaneous determination of Cr, Mn, Fe, Co, Ni, Cu, Zn, As, Se, Mo, Ag, Cd, Ba, Hg, Tl and Pb elements in shellfish was described. The samples were dissolved in HNO₃ by microwave digestion, then the above 16 elements were simultaneously detected by ICP-MS. Correction for matrix effect was made by online addition of internal standards. The correlation coefficients of the calibration curves were all above 0.9992 for all target elements. Detection limits for these sixteen elements were in the range of 6.64×10^-4~0.0851 μg·L^-1. The oyster samples were parallel determined six times and the relative standard deviation (RSD) was less than 5%. The certificated reference materials of scallop (GBW10024) standard reference material were analyzed, and the determination values were in good agreement with the reference values. Due to the advantages of speediness, simplicity, high sensitivity and preciseness, the above method can be used for simultaneous determination of metallic elements in variety of shellfish samples.