Iggy, 26, posted an emotional message confirming the split, and cited "trust" issues as the reason for their break-up.
"Unfortunately although I love Nick and have tried and tried to rebuild my trust in him – it's become apparent in the last few weeks I am unable to," she wrote.
Nick Young and Iggy Azalea started dating in 2013
"I genuinely wish Nick the best," she added. "It's never easy to part ways with the person you planned your entire future with, but futures can be rewritten and as of today mine is a blank page."
Nick, 31, also seemed to confirm the news to his fans as he wrote "Single" on Twitter.
Back in April, Iggy insisted that she and Nick were still engaged, despite rumours that the LA Lakers basketball player had cheated on the Australian rapper.
The pair got engaged in June 2015
A video tape that was leaked online showed Nick allegedly telling his basketball teammate D'Angelo Russell that he had been unfaithful to Iggy with a teenager.
At the time the bride-to-be was also spotted not wearing her engagement ring. She explained that she and Nick were still engaged, but that her future husband would have to "do some work to [see me] put the ring back on".
Iggy's fiancé Nick was caught up in a cheating scandal
During an interview with Ellen DeGeneres, the Fancy singer also denied that she and Nick were going through problems. "It's going good… there isn't [controversy] at home, just on the internet," she said.
"It was gonna happen at the end of the year, but now I have to go to work," she said during an On Air with Ryan Seacrest interview. "We'll probably have to wait until the end of the next basketball season to do that. So that kind of is a bit sucky, but it's all right."