Purpose: In this article, we discussed whether Imam Mahdi is an Antichrist or a Promised Saviour Besides Jesus Christ and other topics. This article attempts to deal with the concepts "Occultation", "Imamat", "Mahdaviat", "Mahdism" and Who is Antichrist that prophesied both in Islam and Christianity. Also, this research was conducted to answer and clarify three questions that stated in the Introduction section.Methods: We performed our methods in 4 stages: Identifying studies, Selection of Studies, Collating Studies, Reporting results.Results: One of the statements of those who say that Imam Mahdi is the Antichrist is that he is not included in other religious books at all and his name is not mentioned in the Quran and the Muslims forcibly accepted him as their Messiah, but in response to these people, it is not the Muslims who are forcibly introducing the Imam Mahdi as a savior, but vice versa. The Quran contains many verses that mention Imam Mahdi. Not only the Quran, but also other religious books mention him, even with the titles and names mentioned in the Qur'an. Conclusion: The coming of Imam Mahdi and Jesus Christ is one of the sure promises of God, and these two saviors will appear with God's help and the will of the people. They fill the earth with justice and establish the government of God. We hope this article will take an important step in acquainting people with Imam Mahdi and Jesus Christ and paving the ground for their reappearance.