Abstract: This paper deals with pollen morphology of 33 species belonging to 5 sections of Dioscorea in China. They were examined under both LM and SEM. The pollen grains of Sect. Stenophora are monocolpate with the size of 17-25.5×26.8-39.1μm, the exine is reticulate, striate, parforate-reticulate or cerebro-reticulate, while those of the other sections are bicolpate, reticulate or cerebro- reticulate with the size of 19.2-26.7×13.9-23.1μm. Based on palynological data Sect. Stenophora may be considered primitive and Sect. Enantiophyllum the most advanced in Dioscorea.

Key words: Pallen Morphology, Dioscorea