Chris Chike earned 840,647 points, a 97 percent completion on Expert Level, for the song "Through the Fire and Flames" by DragonForce, Guinness said.
To mark the launch of the inaugural "Guinness World Records: Gamer's Edition 2008," Guitar Hero players convened in New York City for a jam session.
Chike walked away from the event with the new world record.
"Chris's accomplishments are nothing short of amazing," said Guinness World Records judge Doug Parsons, who was on hand to certify the attempt. "Guitar Hero is one of the hottest games on the market and the speed and accuracy showed by Chris today truly cements his spot as gaming royalty."
Kai Huang, co-founder of RedOctane, creators of the Guitar Hero franchise said in a statement: "The Guitar Hero franchise has created a phenomenon that has swept the world creating loyal and passionate fans of all ages. It is an honor to be a part of this exciting event and we congratulate Chris on a fantastic accomplishment that is worthy of a Guinness World Record."