Abstract: The sample of seafood from Beibu gulf was digested with a mixture of HNO3 and H2O2 (4+3) by microwave assisted digestion, and contents of 7 heavy metals (i.e. Cr, Cu, As, Cd, Sb, Hg and Pb) in the sample solution were determined by ICP-MS. The matrix interference was eliminated by internal standard method. Detection limits (3s) of the method found were in the range of 0.018-0.23 μg·L-1. Tests for precision were made by analyzing a sea shrimp sample by the proposed method, giving values of RSD′s (n=6) for the 7 elements in the range of 1.4%-8.8%. In analysis of two CRMs of yellow croaker (GBW 08573) and scallops (GBW 10024) by this method, the results obtained were in consistency with the certified values.