The singer sparked speculation that new music could be on the way, as she made the surprise announcement on Instagram on Sunday night.
Adele will helm the long-running US sketch show for the first time on 24 October.
Writing on Instagram, Adele said she is “so excited” and “absolutely terrified”.
She wrote: “Bloooooody hellllll I’m so excited about this!! And also absolutely terrified! My first ever hosting gig and for SNL of all things!!!! I’ve always wanted to do it as a stand alone moment, so that I could roll up my sleeves and fully throw myself into it, but the time has never been right.
“But if there was ever a time for any of us to jump head first into the deep end with our eyes closed and hope for the best it’s 2020 right?”
Adele previously appeared as a musical guest on Saturday Night Live in October 2008, also on the eve of the presidential election, and in November 2015.
She said her upcoming hosting “feels full circle”, adding: “It’ll be almost 12 years to the day that I first appeared on the show, during an election…which went on to break my career in America, so it feels full circle and I just couldn’t possibly say no!
“I am besides myself that H.E.R will be the musical guest!! I love her SO much I can’t wait to melt into a flaming hot mess when she performs, then confuse myself while I laugh my arse off in between it all. See you next week.”
Given that Adele’s new album was previously rumoured for an autumn 2020 release, her high-profile slot on SNL has got many believing it could mark the start of her promotional run for an album.
However, we should point out that in Adele’s statement, she refers to hosting SNL as a “stand alone moment” and H.E.R is the musical guest, indicating that the Hello singer will likely not be taking to the stage herself.
It had been highly anticipated her follow up to 2015′s record-breaking 25 would be released in 2020.
However, earlier this year Adele’s manager confirmed it had been pushed back, owing to the pandemic.
Jonathan Dickins told Music Week: “It isn’t coming in September, it’ll be ready when it’s ready.
“We’re all in the same boat, you’re doing stuff and then all of a sudden, the world stops. It’ll come when it’s ready. I can’t put a date on that yet. We have music, but we’re still working.”
In June, Adele also replied to a fan on Instagram who speculated she was about to surprise release the album, commenting: “Of course it’s not. Corona ain’t over. I’m quarantining. Wear a mask and be patient.”