Expeditionary Strike Group 3 is an expeditionary strike group (ESG) of the U.S. Navy. Expeditionary strike groups combine the capabilities of surface action groups, submarines, and maritime patrol aircraft with those of Amphibious Ready Groups for deployment and maintaining staff proficiencies to provide fleet commanders with a highly flexible, ready fly-away unit. It is capable of projecting expeditionary striking power in the maritime, littoral, and inland environs in support of U.S. national interests.

In the United States Navy, the expeditionary strike group (ESG) is a coordinated group of surface ships, aircraft, submarines, and other naval assets. In contrast to carrier strike groups (CSGs), which emphasize air power and are led by a supercarrier, ESGs are strongly suited for amphibious warfare and are led by an amphibious assault ship. The ESG concept was introduced in the early 1990s, based on the Naval Expeditionary Task Force. The U.S. Navy fields nine expeditionary strike groups.