Lee, who co-created the Marvel Comics character with Larry Lieber and Jack Kirby, told DS at the Nickelodeon Kids' Choice Awards that his bit-part role in the movie will be "magnificent".
"I've done that [cameo] already and like all the others it is magnificent. It's the high spot of the movie," he quipped.
"I'm a little sorry about these cameos because people are so affected by them and influenced by them they don't notice what else is going on in the movie. I'm so sorry for Anthony Hopkins and the rest because I steal the thunder. That's the price they pay."
Lee, whose comic creations include Spider-Man, the Fantastic Four and the X-Men, will make his 14th cameo in a Marvel movie when he appears in this month's Thor.
The Nickelodeon Kids' Choice Awards aired in the US over the weekend and will be broadcast in the UK on Friday, April 8 at 8pm on Nickelodeon and nick.co.uk.
Watch the trailer for Thor below: