Taxonomic and demographic studies were conducted on three species complexes withinrnthe genus Aloe L. (Aloaceae) in Ethiopia. The studies aimed to contribute new additionalrnknowledge necessary to delineate the Aloe species and their conservation in the Flora ofrnEthiopia and Eritrea (FEE).In the taxonomic study, the status of 11 species was evaluated using morphological andrnmolecular (AFLP) data. Morphological data were collected from herbarium specimens,rnfresh materials and literature. Data matrices were constructed for qualitative, quantitativernand combined morphological data sets. Molecular (AFLP) data were obtained fromrnleaves of randomly selected germinated seedlings. Total genomic DNA was extractedrnusing a modified 2 x CTAB method described by Doyle and Doyle (1990). AFLPrnanalysis was performed following a protocol modified from Vos et al. (1995). Fragmentsrnproduced by each primer combination were analyzed and scored for the presence (1) orrnabsence (0) of selected markers/fragments. Binary data matrices were constructed forrneach of the primer combinations and also for the combined data set. Each of the datarnmatrices constructed for morphological and molecular (AFLP) data sets was subjected tornmultivariate analyses: cluster analysis (UPGMA) and principal coordinate analysisrn(PCO).The results from the analyses of both morphological and AFLP data supported thernpresent status of nine out of the eleven species: A. harlana Reynolds, A. monticolarnReynolds, A. debrana Christian, A. percrassa Tod., A. yavellana Reynolds, A.rnmegalacantha Baker, A. gilbertii Sebsebe & Brandham, A. calidophila Reynolds and A.rnsinana Reynolds. The boundary between the two caulescent species from the northernrnpart of the FEE area: A. camperi Schweinf. and A. adigratana Reynolds was not veryclear and particularly the genetic delimitation displayed close relationship. The neighborjoiningrntree constructed from combined AFLP data revealed thus weak support for A.rncamperi (51%) and A. adigratana (62%) but kept them together with high bootstraprnsupport (94%).