Issue statement: The Sphinx is one of the types of composite creature’ s motif that theancient man created it with his own mind and imagination and developed it with differentconcepts and appearances during different historical periods. This motif had also appearedin Iran and were used in ancient and Islamic times. Despite the use and significance of theSphinx in Iranian historical periods, this motif has been less studied and is still consideredto be ambiguous. Therefore, in this research, the Sphinx has been studied as widely usedmotif in two historical periods of Iran, the Achaemenid in ancient era and the Seljukin Islamic era. Objective: The purpose of this study is to compare the differences andsimilarities of the Sphinx in the Achaemenid period and the Seljuk period. Research Methodology: The images of the Sphinx during the Achaemenid period and theSeljuk period and its related concepts were searched and based on descriptive method, the characteristics of each were described in the tables separately and the most importantstructural features of motifs were identified. Then, with an analytical approach, the possiblereasons and sources of their application have been discussed and analyzed. In addition, from a visual perspective, they were examined and finally matched together. Conclusion: The results of this study indicate the similarities and distinctions of theSphinx in these two historical periods. In general, it can be said that in the most cases, Achaemenid art and Seljuk art, the Sphinx in terms of structural features are different andin terms of concepts and functional role have many similarities. In the visual examination, it was also found that both of them are similar in terms of composition, rhythm, and typeof script. The Sphinx in the Achaemenid period symbolizes the sun, the power of thekingdom, the protector of the tree of life and palace guardian, the prayers on both sides ofthe tree of life. In the Seljuk period, it is the symbol of the sun, blessing, mystical aspects, constellations, magic, palace guardian, the protector of the tree of life, and the prayers onboth sides of the tree of life.