The Supreme Court of the Commonwealth of the Northern Mariana Islands, 1 CMC § 3101, is the highest court of the United States Commonwealth of the Northern Mariana Islands (CNMI), exercising civil and criminal appellate jurisdiction over commonwealth law matters. It should not be confused with the District Court for the Northern Mariana Islands, which exercises jurisdiction over federal law. The Supreme Court sits in the capital, Saipan, and consists of a Chief Justice and two Associate Justices. The CNMI has no intermediate appellate commonwealth law court, which means that the CNMI Supreme Court hears appeals directly from the trial-level Superior Court.

The Supreme Court was created by commonwealth law on May 1, 1989. This was allowed under the terms of the Covenant to Establish a Commonwealth of the Northern Mariana Islands in Political Union with the United States of America, § 402(c), Act of Mar. 24, 1976, Pub. L. 94-241, 90 Stat. 263, codified as amended at 48 U.S.C. § 1801 note. The Covenant granted self-government to the CNMI, with the U.S. administering the islands under the former United Nations Trust Territory of the Pacific Islands system.

Prior to the creation of the Supreme Court, the Covenant provided that the District Court for the NMI would exercise original jurisdiction over federal law matters and appellate jurisdiction over commonwealth law matters. Covenant § 402(a) & (c). With the creation of the Supreme Court, the District Court's appellate jurisdiction was effectively eliminated. However, the Covenant provided that for 15 years following the creation of a commonwealth appellate court, appeals of that court's decisions would go to the United States Court of Appeals for the Ninth Circuit, just as if the decision was rendered by the District Court. Covenant § 403(a). As of May 1, 2004, CNMI Supreme Court appeals can be taken directly to the United States Supreme Court, thus giving the CNMI court relative parity with the highest courts of the 50 U.S. states.

The court typically hears cases at the House of Justice (Chamorro: Guma’ Hustisia; Carolinian: Iimwal Aweewe) in Susupe; however, some cases are also heard at the Kotten Tinian in San Jose and the Rota Centron Hustisia in Sinapalo.

• 1989–1995 Jose S. Dela Cruz – first Chief Justice and former trial judge
• 1995–1998 Marty Wayne Kendall Taylor – Canadian-born California deputy district attorney and CNMI trial judge
• 1999–2011 Miguel Sablan Demapan
• 2011–2012 Alexandro Cruz Castro (Acting)
• 2012–present Alexandro Cruz Castro

• 1989–1993 Jesus Camacho Borja
• 1989–1997 Ramon Garrido Villagomez
• 1993–1997 Pedro Mangloña Atalig
• 1998–2012 Alexandro Cruz Castro
• 1998–1999 Miguel Sablan Demapan
• 2000–present John Atalig Mangloña
• 2013–present Perry Borja Inos

• Politics of the Northern Mariana Islands

• Official homepage of the Commonwealth of the Northern Mariana Islands Judiciary Archived 2017-03-09 at the Wayback Machine
• Commonwealth Law Revision Commission (with text of the Covenant)
• CNMI Bar Association
• "Northern Mariana Islands", Caselaw Access Project, Harvard Law School, OCLC 1078785565, Court decisions freely available to the public online, in a consistent format, digitized from the collection of the Harvard Law Library