The maize gene mir1 encoded a cystein proteinase which is resistant to fall armyworm. Previously, RFLP map indicated that the mir1 was mapped on chromosome 6. However, physical location of the mir1 gene on chromosome 6 has not been reported. In this study, the mir1 gene was physically located on the short arm of metaphase and pachytene chromosome 6 by dual-color fluorescence in situ hybridization (FISH) with 45S rDNA as a reference marker. The results of Southern blotting suggested that there were sequences homologous to mir1 in Coix lacryma-jobi L. genome. Then, the sequences were mapped on the distal region of long arm of chromosome 7 in C. lacryma-jobi by FISH. The percent distance from the signal site to centromere was 73.33 +/- 0.15.