Objective: Considering that the Qurans of the Ilkhanid period have been prepared in different art centers, the purpose of this research is to do a comparative study of the characteristics of each group and to determine new patterns of illumination in the Ilkhanid School.Methodology: The research method in this article is descriptive-analytical and comparative. In this research, gilded Qurans during the Ilkhanid period in three art centers of that time; Baghdad, Mosul, and Hamadan; Tabriz and Maragheh; and the local versions of Shiraz were studied. Four factors of decorative motifs (calligraphy background), Sar soura format, trances (connected and disconnected), and in-text signs were exemplified and compared.Findings: Some elements of the Seljuk school, such as octahedrons, fringes on the sides of the pages, and the use of circles to obtain decorative patterns were also used in the Ilkhanid period. Knotting or interweaving patterns appeared in the last Seljuk works and became a widely used element in the Ilkhanid period. Based on the use of geometric and non-geometric elements and forms, the gilding of Ilkhani Qurans in three main groups, despite being prepared in the same period, showed different types as distinctive features.Conclusion: The works prepared in different cities show differences, but in general, each of the examined Qurans was prepared in its way based on the book layout principles of the Ilkhanid period. Some elements such as geometric motifs show great progress compared to the Seljuk period, especially in the group of Qurans prepared in Baghdad, Mosul, and Hamadan, and the sample presented with the date 736 (image 20) shows that probably until the end of the Ilkhanid period, gilding with geometric motifs was combined. It has continued with plant motifs in this group. In the works of the northwest, this stage has been completed earlier with the use of plant motifs. In most of the Qurans of the order of Uljaito, which were prepared in Baghdad and Mosul, the background of calligraphy is simple and without decoration, instead, the signs, trances, and inscriptions were made very exquisitely. There is no independent page for the sun in this group; According to Blair's research, this element first appeared in Tabriz and Maragheh Quranic manuscript groups. In the comparison made by Khoddam about the 5-verse toranjs, connected or disconnected toranjs, this element is often seen in Baghdad and Mosul versions along with geometrical, Khata'i, and Islamic elements inside the cedar-like frame. But in Tabriz and Maragheh khatai flower editions, it is also used independently of the circle or cedar frame. According to the research of Khoddam, there were delicate shortfalls around the azure-colored sign from the Seljuq period, and in the Ilkhanid period, changes that radiated with shortfalls (like Shamseh) are seen in the Korans of Tabriz, Maragheh, and three cases in Baghdad. Snak arabesque and inaceolate leaf motifs was introduced as a new element in the gilding of Ilkhanid period. This research also shows that these two roles are abundantly used in the works of all three groups.