The 20-year-old actress and 23-year-old actor started dating 2009 and became engaged last year.
However, the two have now gone their separate ways after Miley’s wild partying ways became too much for Liam.
A source revealed: "Miley and Liam are done; it's over. She likes to party really hard and can be pretty wild. It became a problem for him."
The New York Post also reports that things kicked off between Miley and Liam after she suspected him of having a wandering eye.
A source told the paper:"They have broken up before, and are broken up again now. There was drama because she suspected he had a wandering eye. And she recently tweeted a denial that he cheated.
"While Miley has insisted they are still together, right now they are very, very much apart."
With reports rife that the two were on the verge of cancelling their wedding and splitting for good, Miley took to Twitter to deny the rumours.
She tweeted: "I am so sick of La. And sick of the lies that come with it. I didn't call off my wedding. Taking a break from social media. #draining"
Soon after however, Miley was pictured without her engagement ring while Liam fled LA to be with his family in Australia.
An insider claimed: "He needed to get away from Los Angeles and spend some time with his brother and friends."
Although the two are now allegedly split for now, a close friend of Miley’s has hinted that the relationship isn’t over forever.
They claimed: "Miley is a fiery character, and they do fight, but she is crazy about Liam. She isn't ready to accept it might be over for good."
[Related Story: Liam Hemsworth cheats on Miley Cyrus with January Jones?]
[Related Story: Miley Cyrus and Liam Hemsworth 'take a break'?]