Restriction Fragment Length Polymorphism (RFLP) was used to study genetic diversity in the genera Ananas and Pseudananas. A set of 313 clones was sampled from the collections of CIRAD-FLHOR (Martinique, FWI) and EMBRAPA-CNPMF (Cruz das Almas, Brazil). Most of them were recently collected in Venezuela, Brazil, French Guyana and Paraguay. DNAs were restricted with four endonucleases : Eco R V, Sst 1, Eco RI and Hind III. A partial Pst 1 genomic library was established as a source of RFLP markers. A subset of 25 probes proved to be both polymorphic and to represent low copy number sequences. Data from probe hybridizations were analysed using multiple correspondence analysis and hierarchical cluster analysis on dice index. First results show continuous variation. Species as defined by Smith and Downs (1979) do not appear as separate entities and show large intraspecific variation, especially in Ananas ananassoides. Within Ananas comosus, clones presenting the same leaf margin phenotype such as 'piping' or 'spiny tip' do not constitute uniform clusters. These results are discussed in the context of pineapple domestication. (Resume d'auteur)