This article is to solve the problem on the consciousness of what is true happiness. To solve it, I plan the following. First, I examine the research trends of happiness and argue that we should explore the meaning of true happiness, focusing on anthropological happiness, which defines human happiness as being true human, To this end, I suggest that we explore the concepts of “Eternal happiness” and “Despair” of Kierkegaard who asserted self-realization happiness. Second, through the existential human understanding of Kierkegaard, I prove that human being defined by Kierkegaard is a human being with a task to be existence. Third, Through Kierkegaard’s eternal happiness, I show he reveals that happiness he speaks is existential happiness realizing the true self, human truth, Forth, even if It is despair that can not but be faced in the realization of the true self at this time, I argue that this is the opportunity to go to true self-fulfilling happiness, rather. Finally, I intend to reveal the true meaning of what ‘Eternal happiness’ and ‘Despair’ at the present answer to the happiness that is still being bidden today.