In a previous report, intergeneric somatic hybrids between red cabbage (Brassica oleracea L. var. capitata) and radish (Raphanus sativus L. cv. Shougoin) were produced by protoplast fusion. Plant morphology, chromosome number, isozyme patterns, and SmaI cleavage pattern of chloroplast DNA indicated that the hybrid plants have the red cabbage nucleus and the radish chloroplasts. In this report, we analyzed the organization of chloroplast and mitochondrial DNAs from this hybrid using Southern hybridization. The restriction patterns of almost all regions of the chloroplast DNA from the hybrid were similar to that of radish, except for one region near the rps16 gene, which encodes the chloroplast ribosomal protein S16. In contrast to chloroplast DNA, the restriction pattern of mitochondrial DNA from the hybrid was quite different from that of the parents.