An authentic deed is considered perfect evidence under Article 1870 of the Civil Code (KUHPerdata). Notaries are authorized to draw up authentic deeds, as stipulated in Article 1 of the Law Number 2 of 2014 concerning Amendments to Law Number 30 of 2004 concerning the Position of Notary (UUJN). In reality, errors often occur in deeds, both substantial and administrative, while the UUJN does not explicitly regulate the classification and legal consequences of these errors. This regulatory gap creates legal uncertainty and multiple interpretations of judicial decisions, which risk reducing the evidentiary value of the deed. This study aims to analyze and explain the types of substantial and administrative errors in authentic deeds.