Abstract:Three types of Dioscorea zingiberensis C. H. Wright, the diploid and the triploid from Qina, Yunnan Province, and the tetraploid from Chengkou, Chongqing, were compared by means of examining the morphology, chromosome numbers and isozymes. The results showed that the three types have obvious differences in leaf morphology and chromosome numbers: the diploid, 2n=2x=20; the triploid, 2n=3x=30; the tetraploid, 2n=4x=40. Zymograms of esterase isozyme and superoxide dismutase showed an obvious relation among the three types, but the polyploid ones had less bands and showed lighter-colored compared to the diploid one.