The turbulent events of today, posing new challenges to humanity, in turn, actualize the negative effects and provoke the growth of people's mental tension, anxiety, depression, and crisis, moreover. In contrast, in recent years, there has been a tendency among scientists to understand and conceptualize the concepts of "psychological health" and "happiness", which correspond to the desire of philosophers and psychologists to form new guidelines for overcoming and preventing these negative influences. The article provides a brief historical and theoretical review of the understanding of the concept of happiness in the framework of existential psychology and psychotherapy from the point of view of leading representatives of this field, in particular, S. Kjerkegor, F. Nietzsche, E. Husserl, M. Heidegger, L. Binswanger, M. Boss, E. Van Deurzen, V. Frankl, A. Lengle. KEY WORDS: the phenomenon of happiness, existential psychology, existence, being.