JOY is considered to be one of the basic human emotions and key concepts in culture. The study of emotional concepts is complex as it combines psychological, cognitive, linguistic and ethnocultural fields. The study of concepts is valuable because it enables us not only to identify the culturally specific worldview of a certain lingual-cultural community and single out its national and cultural peculiarities, but also understand the word as a lexical unit in the context of culture, cognition, and communication. The article is dedicated to the research of the emotional concept JOY, its structure and means of verbalization in the Ukrainian worldview. The research is a part of a more complex study which is being conducted by applying the method of cognitive definition suggested by Jerzy Bartmiński ‒ a famous Polish linguist and ethnologist. The source of the material for the research ‒ the electronic corpus of texts "Mova Info", in particular its subcorpus – fictional prose of the Ukrainian literature from the second half of the XX century to the beginning of the XXI century (300 examples). The research showed that the concept JOY in the Ukrainian linguaculture has the following meanings: Joy is a positive feeling, emotion, psychological state, mood, character trait, and can denote a person who causes joy. Joy has different qualities such as duration, sincerity, reality, expectation, frequency, order, degree of control, intensity, depth and volume. Joy is expressed through facial expressions, physiological, behavioral and vocal reactions. The common reasons for Ukrainians to feel joy are universal concepts and values (life, freedom), faith in God, psychological state (love, desire), people (family, friends), humor, jokes, home, objects and phenomena of nature, seasons, material goods, money, gifts, food, drinks, news, important events in life (marriage, child birth), having sex, celebrations, meeting people, mental activities (thinking, learning), entertaining, having a rest, going for walks, travelling, adventures, achievements, success, victory, discovery.