The world olive genetic heritage is very rich in varieties of olive tree (Olea europaea L.), both cultivated and spontaneous, and more diversified is the oil extracted from them. However, this richness is often ignored or misunderstood in detail. Furthermore, taking into account the increasingly restrictive requirements of the oil market and the needs of the consumer, researches on improvement and selection (varietal or clonal) focus on the value of the indigenous varietal heritage and its enrichment through genetic improvement. Usually, the characterization and identification of the genetic resources of the olive tree have been carried out by morphological descriptors related to the different components of the tree (flowers, leaves, fruits, ...). However, these morphological traits have proved to be insufficient and obsolete due to their low discriminating power and their instability linked to the interaction with environmental factors. Recently, new multidisciplinary approaches have been proposed using molecular markers, namely SSR markers, combined with bioinformatic analyses.