This article examines the impact of the UN Law of the Sea Convention on conflict behavior and management in the South China Sea during four periods: during its negotiation (1973–1982); from its signing to the entry into force (1982–1994); from then until the China-ASEAN Declaration on the Conduct of Parties in the South China Sea (1995–2002); and from the setting of a timeline for outer limits of continental shelf submissions to the events following the 2009 submissions (2003–2013). Ambiguous effects were found. On the one hand, the Convention has generated or exacerbated conflict by raising the stakes, failing to resolve key legal issues, and encouraging overlapping zone claims. On the other hand, it has provided obligations, language, and techniques for conflict management and resolution. The conflict-enhancing impact was found to have been more substantial than the peace-promoting effects. Nevertheless, the balance has shifted toward more emphasis on conflict management and also some utilization of the Convention's peacemaking potential. If this long-term trend continues and the Convention is more rigorously respected and applied, the Convention may in the end be found to have contributed to regional peace.