Because of the extreme ecological and environmental changes along an urban-rural gradient, it has been proposed that urbanised and non-urbanised populations of the same species may be distinctly isolated. There is evidence that urban populations have become significantly different from the original forest populations in several aspects. However, little is known about the extent to which urban and non-urban populations are genetically isolated from each other. We tested the hypothesis of genetic differentiation by comparing the genomic DNA of an urban and a nearby forest-living European blackbird (Turdus merula) population. The present results suggest that, based on amplified fragment length polymorphism analysis, the urban population studied is very similar to a forest population at neutral genetic markers. Thus, despite indications of obvious functional genetic adaptation, the hypothesis of an overall genetic differentiation between our urban and forest populations could not be supported.