Hilaria Baldwin is happy to get back to her ballroom roots on “Dancing With the Stars” … so much so, she practically burst into tears after her big debut.

Check it out … an emotional Hilaria chokes back tears while celebrating her stellar Cha Cha routine with Gleb Savchenko.

When host Julianne Hough asks Hilaria to explain her teary-eyed reaction, the yoga instructor explains she never thought she’d be here, given she said “goodbye” to ballroom dance 16 years ago after a hip injury.

Hilaria certainly made a splash with her first performance on ‘DWTS,’ donning a neon green number while Cha-Cha-Cha-ing to “Let’s Get Loud” by Jennifer Lopez. They earned a score of 14 out of 20 for their routine … landing them in 2nd place after night one.

HB was cheered on by husband, Alec Baldwin, and 2 of their 7 children … who looked on proudly after Hilaria hit the ballroom floor.

Despite her ballroom past, Hilaria isn’t necessarily a shoo-in to take home the Mirrorball Trophy … given Robert Irwin made a splash with his jive to “Born to Be Wild” by Steppenwolf — judge Derek Hough called the “best first dance” in the show’s history.