Legal certainty assurance for third parties in disputed land transactions is a crucial issue in Indonesia’s land law system. This study aims to analyze the legal protection available for third parties in land transactions facing disputes. The research method employed is normative juridical with a statutory approach. The findings indicate that third parties in land transactions are at risk of legal uncertainty due to ownership disputes, which may result in the annulment of sale and purchase deeds or legal claims from other parties. Therefore, an effective dispute resolution mechanism is needed, both through non-litigation methods such as mediation, negotiation, and arbitration, as well as litigation through the court system. Legal certainty can be achieved through systematic land registration, adherence to the principle of due diligence in transactions, and legal protection for bona fide purchasers. Thus, this study emphasizes the importance of a strong land law system to safeguard third parties in disputed land transactions.