In humans, the left hemisphere of the brain has a predominant role in the production and comprehension of speech and the right hemisphere in the perception of prosody and emotional content. The laterality for the production of learned song observed in a number of passerine birds is reminiscent of this hemispheric dominance. But we only have few data on perceptual aspects of laterality. The goal of our study was to determine whether song perception is also lateralized. Multiunit recordings were used to test the hemispheric dominance in song perception in six adult male starlings caught in the wild. Neuronal responses to species-specific and nonspecific sounds were recorded in the field L of each hemisphere. In all the birds, there was a slight difference of selectivity between the two hemispheres and a marked difference of activity : neuronal activity during the presentation of species-specific stimuli was systematically stronger in one hemisphere than in the other. On the contrary, this difference of activity did not or hardly existed during the presentation of nonspecific stimuli. Hence, in all the starlings, one of the two hemispheres seemed to process preferentially conspecific sounds. Although we do not know which factors determine this hemispheric dominance nor the nature of this phenomenon, the observation of functional asymmetry is real. Our results suggest that the two hemispheres of starlings perceive and process conspecific signals differently. They add to the many parallels between the avian and human systems that have become paradigmatic of vocal communication.