The Harry Potter actress appeared to confirm her relationship with Adamowicz at the Coachella Festival in California.
The pair were photographed hugging and kissing her partner throughout the evening during the US festival.
Watson has been dating the Boston-based man for around six months, having met at Oxford University, according to the Daily Mail.
Emma Watson is currently in the US to film Sofia Coppola's latest project The Bling Ring.
The star - who turned 22 years old today (April 15) - has previously been romantically linked with actors Johnny Simmons and George Craig.
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