"What I've noticed over the past few months [is] he's kinda used sports to kinda divide us, and that's something that I can't relate to", he told Lemon.
Not long after the tweet went viral, National Basketball Association players came to James' defense.
The White House did not immediately respond to a request to clarify Trump's remarks.
Lemon came to James' defense on Saturday morning, tweeting: "Who's the real dummy?"
White House Bars CNN Correspondent After She Questions Trump
He also said that it was in the interests of Russian Federation and the United States to extend arms control treaties. He later said he had misspoken at the summit.
Michael Jordan, referenced by Trump in his attack tweet, took Lebron's side, releasing a statement: "I support LJ". Last night, Trump tweeted a response to LeBron James' interview with CNN's Don Lemon. I don't want my future kids growing up in a world where two Black men, accomplished in their field, are called dumb because they disagree with your views.
Trump is traveling to OH on Saturday for a campaign rally. White House press secretary Sarah Huckabee Sanders did not return a request for comment, nor did James's agency Klutch Sports Group. The basketball star recently opened an I Promise School for low income and at-risk kids in OH, inspired by his own upbringing.
James also chose Los Angeles in part because it represents the next chapter in his life.
In 2013, Mr Trump tweeted: "Lebron is a great player and a great guy!"
LeBron James listens to a question at a news conference after the opening ceremony for the I Promise School in Akron, Ohio. As James said in the interview, Trump has not only repeatedly over the years, during his campaign and now as POTUS showcased his racist beliefs, he's emboldened some Americans to do the same. I know why. Some of y'all need to start believing what he is showing you.
Attacking Mr Trump, James later tweeted: "U bum @StephenCurry30 already said he ain't going!"