A procedure for the analysis of copper and zinc in blood and blood serum is described. Radiochemical techniques are used for the elimination of interferences such as Na-24. Both Cu and Zn are recovered from a single sample. Analysis time for a single sample duplicated is of the order of two hours. Sixteen samples in duplicate can be processed in approximately 12 h. Mean serum values for normal individuals were found to be 1.54 and 1.20 ppm for copper and zinc, respectively. Mean copper and zinc whole blood values for normal individuals were found to be 1.25 and 8.13 ppm, respectively.