Naval Base Guam is a strategic U.S. naval base located on Apra Harbor, Guam. It is part of Joint Region Marianas, which is a Navy-controlled installation which was combined with Andersen Air Force Base in 2009.

The Ship Repair Facility, Guam, was located next to Naval Base Guam, along Apra Harbor. It was closed due to the recommendation of the 1995 Base Realignment and Closure Commission in 1997.

Naval Base Guam is home of Commander Submarine Squadron 15, Coast Guard Sector Guam and Naval Special Warfare Unit One and supports 28 other tenant commands. It is the home base to dozens of Pacific Command, United States Pacific Fleet, Seventh Fleet, and Seabee units.

Units of Submarine Squadron 15 stationed at Guam include USS Chicago (SSN-721), USS Key West (SSN-722), USS Oklahoma City (SSN-723), and USS Topeka (SSN-754). USS Frank Cable (AS-40) is stationed in Guam to tend the submarines of the United States Seventh Fleet, and the USS Emory S. Land (AS-39) changed from Naval Support Facility Diego Garcia to Naval Base Guam to fulfill the same role.

United States Coast Guard SECTOR GUAM ships include USCGC Sequoia (WLB-215), USCGC Assateague (WPB-1337), and USCGC Washington (WPB-1331).