According to many researchers writting of the great shahnameh was supported by ilkhanids to legitimize their dynasy by making relations between Ilkhanid kings and mythical iranan kings.●PurposeThe current study aims to shed light on the significan role of Shahnameh in legitimation and Persianism of Mongols.●MethodThis artice has been written by the use of discource and liberary method and analysis of important paintings and is based on Foucault’s geneology theory.● Statement of the Problemin this article, persianism means the procces that Mongols went through in order to replace their own culture with Iranian culture and legitimize themselves●ConclusionIt can be inferred from the results that contrary to the initial discourse1 which was based on Ghenghis’s yasa2 that Ilkhanid dynasty is devided into 3 stages: 1.the first one is known for Ghenghis’s invasion and victories in wars and represents terror and fear.2.this stage is called power and domination discourse because of ilkhanid’s attacks that led to conquest of iran.3.at the last stage ilkhanid rulers converted to islam and became adapted to iranian culture. this situation caused the establishment of basics of persianization.Shahnameh was used by Mongols in order to replace themselves with mythical kings of iran. they selectively chose some illustrations of Shahnameh that could be helpful in emphasizing the similarities of the mythical kings and Mongol rulers so that they could be more acceptable for Iranian people. this shows the significant role of Shahnameh on their way to Persianism and legitimation.