To enlarge the genetic diversity of bread wheat, we should utilize more extensively the genes of the related wild species. However, because the morphology of wild species is quite different from that of cultivated wheat, it is not always possible to find useful genes only by observing the wild species themselves. Furthermore, the amphidiploids, such as synthetic hexaploid wheat, are not enough especially in the case of abiotic stress tolerance varying depending on the developmental stage. We should dilute the robust traits of wild species and make a set of wheat lines with a small portion of the wild genome. Crossing and backcrossing a practical bread wheat variety with 43 synthetic wheat lines, made by a durum wheat variety and various accessions of Aegilops tauschii, we made a population and named ‘multiple synthetic derivative (MSD) population.’ This population is a good platform to mine useful genes of Ae. tauschii, such as heat tolerance and long dormancy. The pedigree of the selected plants, if necessary, can be identified by genotyping with genome-wide molecular markers. Because of the pure-line bulked nature, we can easily maintain the large diversity of wild species in the wheat genetic background without separation making many plots. We randomly selected 400 plants from the population and genotyped by the markers. The set of ‘MSD lines’ is a good material to reveal the chromosome location of useful traits in the wild species.