Abstract: Rice is one of thetraditional Chinese foods and its safety is important to Chinese people.Currently, Cd contamination in rice is a serious problem in China. In this paper, 4 rice matrixsamples were developed. During preparation airflow crushing technique wasapplied. Furthermore, IDMS was applied for certification and external additionmethod was used for validating the results. During certification, isobars basedon Sn, Zr, Mo et al were studied. The results show thatisobars of ¹¹²Sn on ¹¹²Cd, ¹¹⁴Sn on ¹¹⁴Cdand ⁹⁶Zr¹⁶O on ¹¹²Cd, ⁹⁶Mo¹⁶O,⁹⁵Mo¹⁶O on ¹¹²Cd, ¹¹¹Cd can beneglected, respectively, but the uncertainties derived from isobars will betaken into account. 4 samples with Cd content of （149.5±3.8）μg/g,（181.8±5.1）μg/g,（387.4±9.3）μg/g,（436.8±13.6）μg/g,respectively are available. The uncertainties derived from certification,homogeneity test, stability test are taken account into the combineduncertainties.