This study aimed to fingerprint 36 water yam (Dioscorea alata) accessions using microsatellite markers. Ten accessions were collected in local markets from several municipalities in Brazil, eight were obtained from the 'Instituto Agronômico de Campinas' (IAC) germplasm collection and eighteen were collected directly from growers from São Paulo state. A total of nine microsatellite loci were used in the analysis. Loci revealed high polymorphism verified by elevated PIC values (0.57-0.77), and by high gene diversity and Shannon-Wiener indices (0.69 and 1.29 on average, respectively). The accessions were classified into two groups based on clustering analysis. One group contained mostly accessions from the IAC collection, including a commercial cultivar acquired in a market in the city of Cuiabá, Mato Grosso state. The second group was composed of most accessions, including those collected directly from growers and markets in São Paulo, a few accessions from the IAC collection, and an accession from Puerto Rico, named 'Florida', which is the most cultivated in Brazil. Several duplicates were identified in this study, including accessions obtained from two farmers in Mogi Guaçu and Mogi Mirim, São Paulo state. However, some of these accessions were allocated in different sub-groups, within this second group. Results suggested the hypothesis of different origins for accessions currently cultivated in Brazil. Similar accessions obtained from different municipalities revealed the commercialization of the same accessions at different locations.