This article evaluates the strategic implications and achievements of the 2023 Beijing Agreement between the Islamic Republic of Iran and the Kingdom of Saudi Arabia. By examining the historical trajectory of Iran–Saudi relations since the 1979 Revolution, the article contextualizes the 2016 diplomatic rupture and the subsequent efforts toward rapprochement. It analyzes the internal and external factors that both enabled and constrained the revival of diplomatic ties, including the role of regional conflicts, changing international dynamics, and the ascendance of economic pragmatism in Saudi foreign policy. Special attention is given to China's mediation and its broader strategic posture in the Middle East under the Belt and Road Initiative. The study reveals that while Saudi Arabia has derived tangible security and economic benefits from the agreement—such as regional de-escalation, improved investment climate, and reduced confrontation risks—Iran's gains have remained largely symbolic and fragile. Persistent asymmetries in expectations, unresolved security concerns, and Saudi Arabia’s limited responsiveness to Iranian priorities have challenged the sustainability of the accord. The article concludes that without institutionalized mechanisms, mutual concessions, and renewed diplomatic dialogue, the current détente is unlikely to last. The Beijing Agreement, while significant, must serve as a starting point for more comprehensive negotiations addressing the structural sources of mistrust and rivalry.