Inter Simple Sequence Repeats (ISSR) technique was deployed for the estimation of genetic diversity in18 Leucaena leucocephala provenances. Seeds of these provenances were collected from across the country and planted at a single location in South India. To estimate the genetic diversity/ polymorphism, DNA was extracted through Cetyl Trimethyl Ammonium Bromide (CTAB) method, visualized and analyzed the DNA bands on UV trans- illuminator gel doc (α-imager 3.2). Totally ten ISSR primers were used in this study. Among them, eight ISSR microsatellites showed a high degree of polymorphism in all the eighteen leucaena provenances used in our study. These primers successfully amplified a total of 645 bands, of which 577 bands (89 %) showed polymorphism. On average, 14.92 bands per accession were obtained and 68.28 % provenances were distinguished through these primers. The ISSR primer T(GT)9 was able to distinguish 100 % of the L. luecocephalla provenances. Cluster analysis based on the genotypic similarities assembled the 18 leucaena accessions in to three clusters. The dendrogram generated based on the 8 ISSR primers distinctively demarcated many of the L. leucocephalla accessions into different clusters indicating vast genetic diversity among the provenances. The high degree of genetic variability demonstrated by the ISSR molecular markers in L. leucocephalla can be used as a tool for assessing genetic diversity and in future leucaena genetic improvement programs.