140 sesame accessions (Sesamum indicum) collected in different regions of Niger were characterized through 16 agro-morphological characters. These characters showed a great diversity within this collection. However, no link has been highlighted between this diversity and the geographical isolation of the collected accessions. The principal component analysis (PCA) and the hierarchical classification on the principal components (HCPC) highlighted three agromorphological groups. The group 1 accessions are the earliest and with a low vegetative development but very productive. Those of group 2 have an average precociousness and a vegetative development but as productive as those of group 1. Group 3 is that of the late ones with a very important vegetative development but low yields. The early rain cessation in September, before the end of their cycle, certainly impacted their productivity. The most discriminating variables that describe the variability between the identified groups are the precocity characters (date of start of flowering, date of 50% flowering, date of start of flower buds and physiological maturity) and vegetation characters (number of branches on the main stem, number of nodes on the main stem and length of internodes). Some accessions, with good agronomic performance, have been identified to be multiplied and distributed directly to producers or to integrate future sesame selection programs in Niger.