Long terminal repeat (LTR)-retrotransposons are mobile genetic elements that are ubiquitous in plants and constitute a major portion of their nuclear genomes. LTR-retrotransposons possess unique properties that make them appropriate for investigating relationships between closely related species and populations. The aim of the current study was to employ Ty1-copia group retrotransposons as molecular markers in cultivated Egyptian cottons, G. barbadense L. Restriction site analysis of PCR-amplified Ty1-copia RT domain promoted the construction of a restriction map for each Egyptian cultivar. These maps display distinctive patterns of restriction site variation. Furthermore, these patterns are capable of differentiating even between cultivars that appear to have diverged only in the past 50 years. These results demonstrate that retrotransposon-based molecular markers are particularly valuable tools for plant molecular phylogenetic and population genetic studies.