The victory of the Islamic Revolution and the neutralization of counter-revolutionary and foreign activities during the early years of the Islamic Republic (e.g., separatist movements, military coups, and the imposed war) resulted from the mobilization of social capital formed during the 1950s and 1960s (Iranian calendar). The significance of drawing on Iranian-Islamic social capital to resolve contemporary crises—especially after the Islamic Revolution—gradually found its place in shaping the notions of governance and a new Islamic civilization in Ayatollah Khamenei’s thought. Consequently, the ideology of the Islamic Revolution was updated and completed by integrating Islamic governance and civilization. This paper centers on the question: What role does social capital play in achieving Islamic governance and a new Islamic civilization? It advances the hypothesis that attaining Islamic governance and a new Islamic civilization is impossible without the support of social capital as envisioned by the Supreme Leader. Thus, the full utilization of social capital capacities is essential for realizing Islamic governance and, subsequently, forming a new Islamic civilization. Findings from a thematic analysis indicate that, in Ayatollah Khamenei’s view, the realization of Islamic governance and civilization depends on two fundamental principles related to social capital. First is people-centeredness, which shows that forming Islamic civilization is unachievable without the will and support of the people. Second, Islam and revolutionary values serve as the most significant social capital for Iranians, providing the roadmap for achieving a new Islamic civilization.