USS Ronald Reagan and ships from its accompanying strike group docked at a naval base in the southern port city of Busan ahead of joint drills with South Korean forces.
Its arrival marks the most significant deployment yet under a new push to have more US "strategic assets" operate in the area to deter North Korea.
Strike group commander Rear Admiral Michael Donnelly told reporters aboard the ship that the visit was designed to build allied relations and boost interoperability between the navies.
"We are leaving messaging to diplomats," he said, when asked about any signal to North Korea, but added that joint drills would ensure the allies were able to respond to all threats.
"It's an opportunity for us to practise tactics and operations," Donnelly said.
South Korean President Yoon Suk-yeol has pushed for more joint exercises and other displays of military power as a warning to North Korea, which this year conducted a record number of missile tests and appears to be preparing to resume nuclear testing for the first time since 2017.
North Korea has denounced previous US military deployments and joint drills as rehearsals for war and proof of hostile policies by Washington and Seoul. The drills have also sparked protests by peace activists who say they raise regional tensions.
Last week the United States said the carrier's visit was a "clear demonstration" of its commitment to deploy and exercise strategic assets to deter Pyongyang and enhance regional security.
In announcing the visit, however, the US Navy made no mention of North Korea, referring only to a "regularly scheduled port visit" and emphasising crew members visiting Busan to volunteer at orphanages and explore the K-pop music scene.
The visit is the first to South Korea by an American aircraft carrier since 2018. Many drills were since scaled back or cancelled due to diplomatic efforts with North Korea or because of the COVID-19 pandemic.
