In conclusion of his Being and Nothingness Sartre articulated the problem of freedom as a moral one, promising to write a book concerning the problem. The work was published only posthumously. As a consequence of it he was reproached by his critics either for the absence of the moral problematic in his existentialism or for that in the long run the moral problem disappears (while the act of a free choice removes the distinction between good and evil). Some of them recognized his moral vision, but only in its negative form (hopelessness, nihilism etc.). In contrast to these views the author tries to show, that the perspective of meaning and values is the core of Sartre’s phenomenological ontology, which is the necessary background of the ultimate objective of the French philosopher: a conception of morals, which would be concrete and historical at he same time. Her argumentation is based on the passages from Being and Nothingness, as well as from Sartre’s posthumous Cahiers pour un morale (Books for a morals). A special attention is paid to problems such as the distinction between ethical anxiety and the everyday mo_rals, the spirit of seriousness, understanding man as useless passion and also the problema_tic of the motive and sense of moral conversion, articulated by Sartre.