Abstract:The karyotypes of one wild and four cultivated lines in Dioscorea zingiberensis C. H. Wright were studied by root tip squash technique. The results showed that the wild was diploid with karyotype formula of 2n=20=14m+6sm. The four cultivated lines were tetraploid, and their karyotype formulae were followed as: 2n=40=20m+18sm+2st for A02-6 line, 2n=40=16m+22sm+2st for A05-6 line, 2n=40=18m+20sm+2st for A09-2-1 line, and 2n=40=16m+22sm+2st for 'hongwei’ line. The karyotype types in either wild or four cultivated lines were 2B, and there were large differences in karyotype not only between the diploid and tetraploid, but also within the four tetraploid lines.