The meaningfulness of life and a desire to immortality has occupied the probe mind for a long time. Belief in the life after death and immortality have a significant role in the human interpretation of meaninglessness of life. Mulla Sadra, based on his philosophical system and foundations such as soul abstraction, substantive movement, physical occurrence of soul and its spiritual survival, and by offering a different and seminal explanation of the phenomenon of death, raised the idea that the its exact understanding verifies the linkage between belief in the immortality of soul and the meaningfulness of life. Mulla Sadra has chosen a philosophical approach to prove the immortality of human soul and, its impact on the issue of meaningfulness is quite significant. considering immortality and meaning in life in his opinion, faith, rationality and morality are colsely associated. In this paper, applying a descriptive analysis, the important components of a meaningful and eternal life are examined and the role of belief in the immortality of soul, in the meaningfulness of life is elaborated according to the principles of Sadraee wisdom.