The ethnic composition, and consequently, the language use and the linguistic landscape of the population of Komárno in Slovakia is continuously changing. The aim of the research on which our paper is based is to prepare the “map” of bilingualism of Komárno. Two autochthonous nationalities live in this town with a Hungarian majority. The research is rooted in a fieldwork carried out using the method of questionnaire survey, and it examines socio-linguistic, sociological and socio-psychological variables. An important viewpoint of the research is to define the nationality and the first language of the informants, since the aim of the project is to make a diagnosis on their orientations and opinions, and to make clear their attitude toward bilingualism, national self-definition and the assimilative tendencies experienced in the town.