The Sunday Telegraph said Beckham arrived at Camp Bastion Friday night, then began Saturday with breakfast and a tour of the camp, home to 9,000 of the 10,200 British soldiers in the country.
"To see the morale of the troops is really incredible," Beckham said. "It first kind of hit me on the way over when we were on the military plane flying in to Afghanistan.
"You can see the faces, you can see obviously they know they are leaving their families, but they're so focused and they've got this look in their eyes that they're just so confident and just ready," he added. "That really is an unbelievable sight to see, and you feel it as well."
Beckham, 35, is missing the World Cup competition because of an injury.