The small population sizes of French local breeds raise the question of their in situ or ex situ conservation. For that goal the characterization of their genetic diversity with molecular tools appears as a preliminary key step. A total of 22 local breeds and 4 commercial lines with an average of 60 individuals per breed were genotyped using a 57K DNA chip leading to a total sample of 26 breeds and 1517 individuals. The commercial lines used as control populations included 2 broilers lines from the AvianDiv collection, one French 'label' slow-growing line and one brown-egg line. Within breed genetic diversity was good but variable (mean F comprised between 3 and 28%), with inbreeding coefficients being negatively related to the size of the selection kernel. Among breed diversity was large (Fst=0.25) allowing for clear genetic identification of breeds. There was no evidence for admixture with commercial broilers but admixture could not be ruled out in the case of one local breed and the brown-egg commercial line. Relationships among breeds were consistent with their history (origin, breeders) or usage (broilers, layers...). Finally, combining these genetic analyses with morphological data could help in detecting genomic regions of interest in a selection perspective. To conclude, French local breeds appeared to be genetically and morphologically diverse making them a good example of a successful management by both breeders and selection centers. Nevertheless attention should be paid on them for long term conservation.