While his remarks were condemned by opponents, China said Wednesday that it's in favor of bilateral talks.
"China supports direct negotiations between the U.S. and North Korea," China's foreign ministry spokesman Hong Lei told reporters.
He was responding to Trump's comments made in an interview in New York on Tuesday that he would pursue face-to-face talks with Kim Jong Un in a bid to persuade Pyongyang to abandon its nuclear weapons program.
Trump added that he would also put pressure on China, which has the closest relationship with North Korea.
This would be a huge departure from current U.S. policy, which has focused on increasing sanctions on Pyongyang in an attempt to force North Korea to denuclearize.
While senior officials in President Obama's administration are in touch with their counterparts in North Korea, there is no contact at the presidential level.
No sitting U.S. president has ever met with a North Korean leader, although former President Jimmy Carter met with Kim's grandfather, Kim Il Sung, in 1994 and former President Bill Clinton met with Kim's father, Kim Jong Il, in 2009.
The Democratic front-runner's senior aide Jake Sullivan said: "Let me get this straight, Donald Trump insults the leader of our closest ally, then turns around and says he'd love to talk to Kim Jong Un?
"I suppose that makes sense for him, since he also praised Kim Jong Un for executing his uncle and seems to have a bizarre fascination with foreign strongmen like Putin and Kim. His approach to foreign policy makes no sense for the rest of us."
Sullivan was referring to Trump's recent feud with British Prime Minister David Cameron, who has refused to back down from calling the New York property developer's proposed Muslim ban "divisive, stupid and wrong."
Earlier this week, Trump responded to Cameron by saying it "looks like we're not going to have a very good relationship."
Trump recently called Kim Jong Un a "maniac" but then seemed to admit that he almost admired the way the North Korean leader had strengthened his grip on power.
"How many young guys -- he was like 26 or 25 when his father died -- take over these tough generals, and all of a sudden... he goes in, he takes over, and he's the boss," said Trump.
"It's incredible. He wiped out the uncle, he wiped out this one, that one. I mean this guy doesn't play games. And we can't play games with him."
North Korea first tested nuclear weapons in 2006, in violation of international agreements, and has made repeated threats of nuclear strikes against South Korea and the United States.