James, 29, a two-time NBA champion, will attend the final between Germany and Argentina at the Maracana on Sunday.
"This is the highest you can get," he said.
"This is bigger than the NBA finals in the sense that it's the world and you have so many countries here."
The NBA star is a minor shareholder in Liverpool and claims to have been a fan of football "for a pretty long time".
He declined to pick a winner in the World Cup final but claimed Germany are a better overall team than Argentina.
"I'm not sure," he said. "I think Germany is the better overall team, but Argentina has one of the best players in the world -- maybe the best, [Lionel] Messi.
"So that's why we play the game and we'll see what happens. I hope it's a great one.
"I've been watching it from home in the States and it's been an unbelievable tournament."
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