Jennifer Lopez almost landed on her “Booty” during her Las Vegas residency … just barely catching herself after slipping onstage.

The singer-songwriter took the stage at The Collosseum at Caesars Palace for her “Jennifer Lopez: The JLo Show Live” Friday night … when she was ironically belting out “On The Floor” — which she almost ended up on herself.

Check out the clip — posted to social media by reporter John Pascarella — during a quick turn onstage, J Lo momentarily loses her footing.

J Lo’s been performing for years … and she’s had her fair share of mishaps onstage — including last year when her skirt completely came off at a show in Poland.