Considering some contemporary aspects of the geographical regionalization and administrative-territorial organization of Croatia, the author introduces the thematic through a retrospect of geographic thought development in the question of regionalisation. Main changes in administrative-territorial organization of Croatia from World War II to the beginning of the 21st century as well as some problems of applying geographical regionalization principles in the defining of regional units have been discussed. Finally the characteristics of the actual regionalization in Croatia have been analysed and an attempt of defining the functional regionalization of the country in the contemporary circumstances at the beginning of the 21st century has been given.