The Drosophila strains v;bw and Austin represent the extremes in resistance and sensitivity, respectively, to the toxic effects of CdCl2 in the diet. Using the six genotypes containing the possible combinations of the three main chromosomes for v;bw and Austin, we had shown previously that the gene(s) for cadmium resistance is on the X-chromosome. In this paper it is shown, using the same six genotypes, that the gene(s) for strontium resistance is on the second chromosome, as measured by LC50 values.