The 24-year-old Canadian singer reportedly popped the question on Saturday evening.
The pair got engaged in the Bahamas during a vacation with friends.
According to eye witnesses they were at a restaurant inside their resort doing salsa dancing when Justin's security told everyone to put their cell phones away.
They explained that something special was going to happen before Justin proposed in front of everyone to his 21-year-old model girlfriend.
The couple has been inseparable over the summer and started dating around a month ago.
The couple has a history and it appears they hooked up again just after Justin and Selena Gomez broke up.
And his family seemed to be pleased about the engagement news.
His father Jeremy, posted a photo of Justin Sunday with the caption: "@justinbieber proud is an understatement! Excited for the next chapter!"
RadarOnline.com reported that they were getting cozy in The Hamptons recently.
Congratulations to the happy couple!
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