In the illustrated manuscripts of Ferdowsi’s Shahnameh, the Simurgh is depicted as a dual symbol—both “sacred” and “demonic.” Based on Mircea Eliade’s theory of mythology, this duality contrasts the Simurgh’s wisdom-bestowing role in the story of Zal with its destructive function in the Seven Labors. Eliade’s approach interprets reality through the re-creation of “primordial time,” and the Simurgh’s symbolic duality reflects the inherent paradox of the sacred—its simultaneous allure and terror. This study aims to analyze the symbolic role of the sacred and demonic Simurgh in Shahnameh illustrations through Eliade’s theoretical lens. The central question is: How has the Simurgh’s symbolic representation, within the sacred/demonic duality, been shaped in these manuscripts? The research employs a descriptive-analytical method, with data gathered from library sources. The corpus consists of five prominent illustrations from distinguished Shahnameh manuscripts of Persian painting schools from the 8th–10th centuries AH, each portraying the Simurgh in sacred and demonic forms. Findings show that the illustrated Simurgh embodies the manifestation of the transcendent in the material world, expressing a dual function and cosmic connection. On one hand, it acts as a healing force and a source of life and order; on the other, it becomes a destructive power—what Eliade terms the “terrifying aspect of the sacred.” As the axis mundi in Eliade’s framework, the Simurgh appears at pivotal moments in the Shahnameh—birth, crisis, and death—reviving archetypal patterns and shifting the epic from linear history into sacred time. The transformation of the Simurgh’s role narrates a passage from myth to history, corresponding to what Eliade calls the “collapse of the sacred,” leading to the desacralization of the world and a rupture from mythic memory.