Seventy landracc accessions and eleven genotypes were used for morphological and ISSRrndiversity study. The plant materials were grown in a simple lattice design of two repl ications forrnmorphological di vers ity s tudy at Sinana Agricult ural Research Center. Ten plants were selectedrnrandomly frolll each accession/genotype and marked before flowerin g. Morphological data werernrecorded from all selected plams on cleven trailS. DNA was ex tracted fro Ol a bulk sample of fi vernplants using a triple CTAB extraction technique. Molecular data were generated using lour ISSRrnprimers. ANOVA of morphological data indicated significant differences among the pl antrnmaterials. Estimmcs of phenotypic and genotypic coeffic ien ts o f vari ation showed widerrnvariabili ty within and between the landrace popula tions and betwccn land races and exoticrngenotypes for different morphological characters. Morphological dissim ilarity between thernpopulations ranged from 0.05 19 to 0.73. Clustering anal ysis based on morphologi cal di ssi milarityrnmatrix re vealed three groups wi th distinctive morphological traits. The wider phenotypicrnvariability observed encourages improvement acti vities between the lentils. Molecular analysis,rnon the other hand, showed that exotic genotypes were more diverse compared to the landraces.rnGenetic di versity with in the total landrace population (I-I r) was 0.1734. !-ligh AR-based geneticrndiversity (0. I 395 - 0.1039) was observed for samples from Gonder. Shewa and Well o. lI ighrnwi thin GR divers ity was obtained for samples from NEE and the least for those from SEE. Exoticrngenotypes were more di stantly related with samples frolll Tigray, Gojam and Shewa than tornothers. The genetic di stances between populations of Ethiopian lentil land races ran ged fromrn0.2284 - 0.0 12. Samples from CE were more distantly related to samples of SEE. while therndi stance between other GRs was relatively low. Es till1 ates of population difTerent iat ion and genernnow were moderately high ror ARs. On the other hand. GR-based population difTerentiation wasrnlow, whereas among GR gene flow was high relative to AR-based population di fferentiation.rnAMOVA revealed higher within population variation than among population. Cluster analysisrnbased on Dice's s imilarity coefficient revealed three groups with di stinct molecular proliles bothrnwi th and without exotic genotypes. There were high ly s ignificant (p < 0.00 1) corre lations, r =rn0.45 and r = 0.26, between morphological and molecular distance matrices, respecti vely, of thernentire pl ant materials and landraces separately. implying the vali dity or both methods forrndiversi ty study in lentil s. Observation of low ith in ARlpopulation divers ity invi tes fu rtherrncollection ac ti vities. while enriching populations with high genetic diversity.