The couple, who have been together for three years, met on the set of the film, The Last Song.
Hemsworth, 22, popped the question on May 31 with a 3.5-carat Neil Lane diamond ring, reports People.
On Wednesday, 19-year-old Cyrus tweeted, “Thank you for all the love today I’m happy to share this news with you all. I feel like all my dreams are coming true. ❤ have a great day.”
No wedding date has been set yet.
Over the years, there have been repeated, engagement rumors, but this time it’s the real deal.