Chuck Liddell is psyched he got to film with the Kelce brothers … telling TMZ Sports that, despite their enormous fame, Travis and Jason are super humble dudes!

We saw the retired MMA superstar at the L.A. premiere for “Kill Me Again,” (directed by ex-MMA fighter turned actor Keith Jardine, who we also spoke to!), just days after we got behind-the-scenes footage of Liddell kickin’ ass (literally) in the Kelce’s Garage Beer short film.

“It was great!” Liddell said outside the theatre.

Liddell — who last fought in November 2018 — seemingly didn’t know what to expect going into the gig … as he was going to be working with two of the most famous people in all of sports and entertainment.

“They were down to Earth,” Lidell said. “You know, you hear things about people, but they’re just good ol’ boys.”

Of course, we had to ask Chuck if he got a chance to meet Travis’ superstar girlfriend, Taylor Swift.

“No, I heard he took off early to meet up with her. I don’t blame him,” Liddell laughed.

Maybe next time!

And, speaking of acting, we also talked to Chuck (and Keith) about his film, his directorial debut, which Jardine also wrote.