Nineteen-year-old Matt Guthmiller completed the more than 29,000-mile journey in a single-engine airplane Monday night when he touched down at Gillespie Field in El Cajon, California.
Guthmiller's flight began May 31. His final, 16-hour leg took him from Honolulu, Hawaii, over the Pacific Ocean to El Cajon.
The Aberdeen, South Dakota, native was greeted by reporters and his mother in El Cajon. He says "it's great to be back."
The previous record was set by Australian Ryan Campbell who was 19 years, seven months and 25 days old when he completed the circumnavigation last year. Guthmiller will be that age on July 24.
Guinness World Records didn't immediately respond to a message early Tuesday.