A study of diversity was performed on 81 wild Helianthus annuus populations sampled from North America. Morphological and development traits were evaluated for different organs. Principal component analysis of quantitative traits associated the first components 1) to precocity-related traits in agreement with the geographical origin of the populations and 2) to domestication traits. We did not find any structure of qualitative traits by correspondence analysis. A sub-sample of twenty-one contrasted populations was observed for RAPD in comparison with twelve cultivated sunflower inbred lines. One hundred and seventy four polymorph fragments were revealed using nine primers. Cultivated inbred lines were unambiguously separated from wild populations by any analysis. Using RAPDs, much more diversity of wild Helianthus annuus appears in comparison with cultivated sunflower inbred lines. Among these populations, no reliable structure or clusters were found. We inferred from these results that a great deal of polymorphisms among wild Helianthus annuus remains to be investigated for possible use in sunflower breeding. We inferred also that it was not possible to ascertain clear structures of any qualitative traits and RAPD for wild Helianthus annuus populations. This absence of structure could be related with the dispersal of these wild resources when used by nomadic early Americans.