Doechii went for a wild ride — actually more like a crash-landing — down a slide … lingerie and zero grace included!

Catch the clip — Doechii was belting out “Denial Is a River” at her Madison Square Garden show Monday when she strutted up to the slide on stage … but her graceful ride down went sideways when her heel snagged.

It’s comedy gold … she flips onto her belly mid-slide, with her lingerie-clad booty stealing the spotlight.

Stuff like this is par for the course with live concerts … and Doechii didn’t miss a beat. Total good sport, and she laughed it off and kept the show rolling.