Starches from ten yam (Dioscorea) species were compared with those of maize, wheat, potato and cassava, and characterized by high-performance size-exclusion chromatography coupled with multiangle laser light scattering. Treatment with 95% (v/v) dimethylsulphoxide and microwave heating in a high-pressure vessel led to complete dissolution of the starch samples. For yam starches, Mw were between 1.88 x 108 and 3.27 x 108 g mol-1 and Rg were between 258 and 396 nm. The hydrodynamic coefficients of amylopectins were between 0.36 and 0.44, indicating that those of maizes and esculenta 5 and dumetorum yam species had particularly highly branched structures. Multidimensional analysis of the macromolecular characteristics of yam starches indicated three classes: dumetorum cultivar (Dioscorea dumetorum), esculenta 5 cultivar (Dioscorea esculenta) and the other eight yam starches, including cultivars of Dioscorea alata and Dioscorea cayenensis-rotundata species. Some yam starches were also leached at 90°C. The macromolecular characteristics of the leached fractions confirmed the previous typology.