The 45-year-old "The Martian" star, who is back in the fifth installment of the Bourne franchise, said he knew he would be replaced someday, said the Hollywood Reporter.
"(I am) definitely going to be replaced some day by some new young Jason Bourne. That happens to everybody and they reboot these things, and that's totally fine," he said.
Speaking on a promotional tour in Seoul, South Korea, Damon, who returns for the fifth installment titled "Jason Bourne", said, "The only control I can exercise is over the ones that I'm part of."
"It's difficult when you're 45 compared to when you're 29, but you still have to run as fast as you can. That part was a challenge but to get to revisit the people was wonderful.
"You'll see what you've seen before (in the upcoming film) and will recognize it as a Jason Bourne movie but it feels new and of the world we're living in today," he added.
Directed by Paul Greengrass, "Jason Bourne 5" is set to release on July 29. The movie also stars Julia Stiles.