Lately the number of Money Laundering Crimes (TPPU) in Indonesia has been increasing, both in terms of quantity and quality. The perpetrators tried various ways to find a safe position in committing TPPU, even by utilizing the services of a notary. The vulnerability of TPPU which involves the services of a notary in an effort to hide the origin of assets obtained through a crime is the main cause of the application of the Principle of Recognizing Service Users (PMPJ) for Notaries. So that notaries must be extra careful in serving their clients as service users, this is as stipulated in Law No. 8 of 2010 concerning the Prevention and Eradication of Money Laundering Crimes (UU PPTPPU) and Government Regulation (PP) No. 2 of 2016 concerning Procedures for Submission of Data and Information by Government Agencies and/or Private Institutions in the Prevention and Eradication of Money Laundering Crimes. According to these provisions, a Notary is one of the reporting parties who has the obligation to submit a report on suspicious financial transactions. So it is necessary to conduct a study on the role of a notary in implementing PMPJ as an implementation of the precautionary principle.