Gisele Bundchen is going to the Met Gala tonight -- and she'll be going by herself in what we're told will amount to a major fashion statement since her split with Tom Brady.

Sources with direct knowledge tell TMZ the supermodel will join the annual pageant in NYC, dressed to the nines with all the other celebs streaming into the museum. We're told she'll be wearing Chanel in honor of its late creative director Karl Lagerfeld.

Karl and Gisele had a long relationship, and our sources say her appearance will be a nod to their working history ... which might have reached its peak when Gisele was tapped to be the face of Chanel N°5 perfume almost a decade ago.

Gisele's return to the Met's a big deal for a couple reasons. One, it's her first time since divorcing Tom Brady. Secondly, it's her first time going as a single woman since 2006.

The ex-power couple attended together for years, but as many know, Gisele had a history of showing up and owning the moment well before she ever got with Tom -- and we're told she'll be returning to fashion first mode with tonight's appearance.

The last time Gisele went was in 2019 ... on Tom's arm -- but tonight she'll have the spotlight all to herself.

Of course, one can't help but wonder about her new may-bae -- the jiu-jitsu instructor, Joaquim Valente, with whom she's spent a lot of time in Costa Rica. Our sources have insisted they're not romantically involved whatsoever, but even if they are secretly dating ... it sounds like he's gonna have to sit this one out.