"That's false," Trump said as a reporter began his question.
Asked whether he called rapper Lil' Jon an "Uncle Tom," Trump said, "I don't know who Little Jon is."
He was reminded Lil' Jon was on his NBC show, "The Apprentice."
"I would never do that and I don't use racist remarks," Trump told reporters in the East Room, adding that if he did, "You would've known about it."
Trump said he "never" worries about any record of racist remarks because "I have never used racist remarks."
The exchange came after Trump told an African-American reporter that her question on white nationalism was racist.
Asked about his support for nationalism and if it might embolden white nationalists, Trump said: "I don't know why you'd say that. Such a racist question."
"To say that as you said that to me is so insulting. It's a very terrible thing what you said," the President said. "Why do I have among the highest poll numbers with African-Americans?"
"That is such a racist question. Honestly, I know you have it written down and you're going to tell me 'What do you think?' That is a racist question," he continued. "I love our country. I do. You have nationalists. You have globalists. I also love the world, and I don't mind helping the world, but we have to straighten out our country first."