Abstract: The quality of a series of uranium calibration standards and a series of plutonium calibration standards for the segmented gamma scanning(SGS) was verified. It is important to analyze the proper quality of the special nuclear material in the standards and its homogeneity in the matrix was measured by gamma ray non-destructive assay (NDA). As a result, the measured values of each series standards are agreeable withdeclared within 1%. And the measured results of the material uniformity in matrix for both series of the standards are better than 3%.