The reality star selected Gaga as the headlining act of his popular Miss Universe Pageant in 2008, and during the show the singer performed her breakout song Just Dance for the very first time on TV.
After making her international debut on the programme, Gaga shot to fame - and Trump is certain he had a hand in giving the hitmaker her start.
He says, "I own the Miss Universe Pageant. And about four years ago, during what you call half-time, we always have an entertainer. We've had a lot of great people, and you don't pay them anything because it's one of the biggest audiences and my people told me, 'Nobody knows who she is but there's this woman with good talent named Lady Gaga.' And I said, 'Give me a break.' And then they said, 'She's really good.'
"So I said, 'I don't care, if you like her, put her on.'
"So we put her on... it was live all over the United States and all over the world and the next day, nobody was talking about (the winner of) Miss Universe, everybody was talking, 'Who was the woman, who was the entertainer? She was unbelievable.'"
And Trump reveals Gaga has been forever grateful he took a chance on her: "She's been very gracious about it... About a year ago, when she was so hot, and she's hot now, she was performing at Radio City Musical Hall and there were a lot of celebrities, all sitting next to me, and her manager came up during the performance and said, 'Gaga wants to see you, but only Donald Trump.'
"And it was embarrassing because of all these people and she remembered. I don't want to say we made Lady Gaga, but she was incredible and that was her break."