The relationship between the Imamate and the ending of prophecy, Nubuwwa, is an important Issue of discussion. The study of this will be possible by separation of the positions of Imam and knowing its quality. According to the guidance of Quran and Hadith the knowledge of allowed and forbidden (Halal and Haram) and also of Holy Quran is transmitted to the Imams by the prophet. So the role of Imam to this knowledge is explaining and interpreting and Imam is a criterion for resolving of dissension and revealing the transmitted knowledge. In addition to the status of sublimating and realization of the end of the prophecy, Imam possess the position of especial Guidance. Therefore the position and status of the Imam necessitate his appropriate knowledge. In fact, by the ending of the prophecy, the era of descenting and canonization is overed as well, but it does not imply the end of all status and the functions of prophecy.