Among the verses of the Quran which indicate the necessity of a living proof at all times are verses related to the witnesses of deeds. The present research seeks to answer this question that how the life of Imam Mahdi (A.S) can be proved considering the verse of attestation. According to the findings of the research, God the Glorified, places a special person from among the ummah as a witness of their deeds at all times and all nations, to testify about the performance of the ummah in the Divine Court on the Day of Judgment. This divine tradition goes on in the ummah of the last Prophet (PBUH), thus, the presence of a witness at every age and time, including the present time is necessary. Such a person should have the status of infallibility and observation of the reality of the deeds. This paper is carried out with a descriptive-analytic method and to examine and analyze the verses of the Holy Quran, we have benefited from the method of interpreting the Quran with the Quran.