Subject matter of the Islamic Sufism is the Unity and unitary, i.e. Perfect man and there are many deep and valuable conversations about that as one of the main fundamentals of Islamic Sufism. One of the clear characteristics of a perfect human is the knowledge. This research aims to study the nature of knowledge from SeyyedHeidarAmoli’s Point of View. Results of the research are as follows: Seyed Heidar Amoli’s had shown the comprehensiveness, originality and superiority of perfect man’s knowledge via establish the relation between knowledge and the intuitive knowledge between with the aim of triple (Sharia, Tariqa and haqiqa), also Elm-Alyaghin, Eyn-Alyaghin, Hagh-Alyaghin. Thus, he believes that nature of the knowledge of perfect man is the same as intuition and its components are: comprehensiveness, continuity, holly assurance, instant, inherited, blessing and originality. Seyed Heidar, also has determined the knowledge of perfect man in two Accenting and descanting ways based on personal unity and with the aim of union. Moreover, as a Shiat, he believes that Prophet Mohammad and Imams are samples of perfect man.