Manuscripts are among the most valuable works which being studied can help discover the hidden figures of culture and art. Meanwhile, as one of the most important places, the museum plays an essential role in preserving exquisite works such as manuscripts and other historical works through time. Works such as manuscripts and illustrations have a special place in the field of Iranian painting in terms of studying Iranian-Islamic identity and art. In this article, the main part of which is based on library and documentary research, the visual structure of some illustrations of Ferdowsi's two Shahnamehs, which are valuable literary and artistic manuscripts preserved in Saadabad Palace-Museum, is examined. The purpose of examining the illustrations of these two illustrated Shahnamehs is actually to examine and introduce these two rare and unknown versions and, on the other hand, to introduce treasures of the noble art of Iran. The two versions of Shahnameh in question were illustrated in two different periods, but they clearly have features that are completely worth studying in terms of special visual effects. Examining the structure and unique features of these two artistic masterpieces results in more familiarity with the elements that make up the paintings, the type of color and coloring, composition, etc., used in both works, which are important for more studies in the future. In each of the studied Shahnamehs, despite the similar themes, unique characteristics were observed that show the independent identity of each.