The purpose of this research is to convince the urgency of external supervision on Constitutional Court‟s Justices in Indonesia. The research focuses the study on the importance of external supervision on Constitutional Justices in Indonesia. The research is a normative legal research which uses Constitutional approach, statute approach, and comparative approach. The result of research shows that there is urgency of external supervision on Constitutional Court‟s Justices in Indonesia. Urgency of external supervision on Constitutional Justices is due to some reasons. First, supervision system against the behaviour of Constitutional Justices is not maximum yet and not ideal. Second, when it compares between system supervision of judicial institution in other countries, author arrived at the conclusion that other countries gave authority to the Judicial Commission in supervising the judiciary. Third, the position of the supervisory institution of Constitutional Justice is still internal and not a maximum of control and does not guarantee the performance of the Court because the cases of Constitutional Justice is still going on. Responding the unclear authority of the Judicial Commission in Supervision the Constitutional Court Justices, the People‟s Consultative Assembly (MPR) needs to amend Article 24B of the 1945 Constitution which asserts the authority of the Judicial Commission in supervising the Constitutional Court Justices.