Sydney Sweeney Shows Off PDA with Fiancé While Picking Up Bags at LAX

Sydney Sweeney and her fiancé are already looking like man and wife -- 'cause they were all loved up at the airport ... showing off their affection to anyone who wanted to look.

The actress and her hubby-to-be, Jonathan Davino, touched down at LAX Thursday night ... coming down the escalator at their terminal and heading over to baggage claim to get their belongings. Of course, paps were on hand and firing away ... capturing the whole journey.

Syd and Jon were putting on a lot of PDA as they made their way to the airport carousels ... and once they were there, they topped it all off with a cozy hug from behind.

Check it out ... Jon wraps his arms around Sydney as he stands behind her -- and the two of them looked absolutely head over heels ... which, frankly, is always how they come across when they're together. More importantly ... they're clearly comfortable while in public.

One other thing about this ... there was something wrapped around Jon's left ring finger -- and while some have speculated it's a band of some sort, it's actually just a hair tie.

Anyway ... it's just the latest outing between them, and as Sydney's star continues to rise -- she continues to lean into the fact that she's engaged and in a happy relationship ... which we're sure is pissing off a ton of dudes who are thirsting over her as the newest bombshell.

Remember, there was some speculation Sydney was into her rom-com costar Glen Powell while they were promoting "Anyone But You" last year ... but as we've come to learn, it was all PR and nothing but a marketing stunt ... one that Sydney apparently concocted herself.

As it turns out ... she's more than happy with Jon, with whom she's been with for years now.