Herschel Walker -- My Son's a World Champ ... Crushed Huge Cheerleading Tourney (VIDEO)

Herschel Walker's 16-year-old cheerleader son did something the ex-NFL star never did ... WON A WORLD CHAMPIONSHIP -- and Herschel says he couldn't be more proud!

Herschel was out in D.C. Tuesday when we asked about Christian Walker -- a member of the Spirit of Texas Royalty co-ed cheer squad ... which just took home the title at the 2016 World Championship of All Star Cheerleading at Disney World.

"I was so thrilled about it because there was a lot of good competition there," Herschel told us ... "but I'll tell you what, they got it done!"

BTW, Herschel also has a message for the haters who don't respect cheerleaders -- they're REAL-DEAL athletes!!

"It's a tough workout. I've been at some of the workouts ... I challenge anyone out there, 'cause I know about working out ... and I'll tell you what, they get a tough workout."

Congrats!