Abstract: The species Tropaeolum pentaphyllum Lam. (batata-crem or crem) is of great economic and medicinal importance. For being an endangered species, the knowledge of its genetic variability is necessary. Considering the lack of cytological studies on this species, this work describes the chromosome numbers, the meiotic behavior, the meiotic index, and the viability of the pollen grains of three populations of T. pentaphyllum from Rio Grande do Sul, Brazil. The three populations presented 2n = 28 chromosomes. Meiotic behavior was regular, with low abnormality frequency (<1%), which culminated in IMx> 90% in the three accessions. This meiotic stability resulted in high production of viable pollen grains, which will favor the use of these accessions in selection programs for commercial purposes, conservation and sustainable use.