Lauren Boebert was living her best rock star moment 'cause she was caught totally fangirling over Kid Rock at the inaugural ball in D.C.

Sources close to the situation say Lauren and her mom are big KR fans  -- and you can totally tell from this video Sunday that the excitement was real.

Lauren was totally transfixed by the rock star, yapping away, doing a little dance, and clapping like she was front row at his concert -- basically giving Kid Rock all the hype he needed.

They weren’t alone -- controversial comedian Tony Hinchcliffe was there too, just months after his offensive Puerto Rico "garbage" joke sparked backlash.

It was a big night for them all -- especially with Lauren and Kid being all-in supporters of Donald Trump -- now officially sworn in as the 47th President of the United States.

By the way, Boebert is not only a huge fan of Kid Rock ... but she also loves Beetlejuice!

You may recall ... she was famously booted from a Denver, Colorado, theater while attending a 2023 "Beetlejuice" stage production ... after patrons complained about her vaping and getting handsy with her date.