Methodology: In this research, by examining some of the functions of religion using descriptive-analytical way, the library and software resources have been used Findings: By analyzing and finding the roots of psychological problems and crises such as absurdity and meaninglessness in life, fear of death, escape from loneliness, impatience, confusion and despair, it can be understood that human beings have unlimited and sublime tendencies other than instinctive and physical tendencies. The central tendency among these tendencies is human perfectionism, which is the difference between humans and animals. However, it is impossible to reach this innate and unlimited tendency in the limited material world, and it leads a person to a contradiction and an intellectual and belief impasse. Results: Corresponding to the findings of the research, it can be said that human perfectionism has a central role in the functions of religion. This desire for human perfection within the framework of the material world becomes the basis and the real cause of human spiritual and psychological problems because the source of perfection is beyond the material world. In fact, only the divine religion can free man from this belief impasse and respond to this original and real need of man. Background and objectives: Religion, as a divine gift, has always had an effective and decisive presence in the heart of human societies. In this research, some of the most important functions of religion in human mental health have been examined, which include giving meaning to life, looking positively at death, saving from the swamp of loneliness, strengthening patience and stability, and the effectiveness of prayer. The question here is: Is there a special relationship between man and religion? What is the role of human perfectionism and its relationship with the functions of religion?