The field of auditory recognition of words occupies an important place in cognitive psycholinguistics. The study of the processes and representations in the recognition of words is an extremely complex activity, which depends on the physical characteristics of the signal, the requested sensory method and the forms of organization in mental lexicon. The present study investigates the process of auditory lateralization by Arab/French bilingual subjects. The originality of this study is closely related to Arabic/French and diglossia situation in Algeria. Twenty-five bilinguals mix Arabic and French in their oral speeches, and another twenty-five French were selected in studying the process of lateralization. A dichotic listening technique used in sending two different words simultaneously to each of the ears was adopted, whereby every subject was asked to report what s/he perceived. The finding of the experiment showed more words were reported in the right ear regardless of language.