The US pop singer posted images on Twitter and Instagram of her kissing and embracing the Australian star while wearing an ivory gown.
Cyrus also shared a video of her producer Mark Ronson whistling Here Comes The Bride.
The Wrecking Ball singer later posted a clip on Twitter of herself dancing after the small ceremony in Tennessee.
An image she posted on Instagram carried the caption "12.23.18", which is reported to be the date of the wedding.
Two other photos had the captions "This is probably our one - millionth kiss" and "10 years later" in a likely reference to the film The Last Song.
Hemsworth played Cyrus' love interest in the coming-of-age teen romance.
The pair's relationship is said to have started during the making of the 2010 film.
Some details of their wedding appeared online last week, including photos of Hemsworth's brothers Chris and Luke at the wedding and the married couple cutting the cake.
© Sky News 2018