The young man, who began shouting and waving a piece of paper as the president riffed on Rep. Ilhan Omar, D-Minn., was humiliating his family, Trump told the adoring crowd.
"He goes home now to Mommy and he gets reprimanded and that's the end," he said.
"Sorry, Mom, didn't mean to embarrass you," the president added, imagining what the man would tell his mother after being evicted from the Greenville event.
Security personnel could be seen leading the man out of the arena with his hands behind his back. At one point, the man whipped his head back to discard the Make America Great Again hat he was wearing.
Prior to the outburst, Trump was in the midst of responding to criticism from the so-called progressive "squad" -- who he sparred with earlier in the week on Twitter.
"They've gone so far left, no one wants to think about it," he said. "Representative Omar blamed the United States for the terror attacks on our country, saying terrorism is a reaction to our involvement in other people's affairs," he said.
Trump claimed Omar was "minimizing" the September 11 terror attacks by remarking in an interview, "some people did something."
Earlier in his speech, the president dismissed the Russia investigation as "bulls--t," appearing to credit a person in the crowd with thinking of that description.
"What happened to me with this witch hunt should never be allowed to happen to another president of the United States, never ever again," he said.
The rally was also Trump's first appearance since a developing feud with progressive Democrats, and a string of comments they slammed as "racist."
"I just heard that the United States House of Representatives has overwhelmingly voted to kill the most ridiculous project I ever worked on" Trump said at the top of his rally -- referring to an impeachment resolution proposed by Rep. Al Green, D-Texas.
"The resolution-- how stupid is that-- on impeachment."
Fox News' Vandana Rambaran contributed to this report.