The visit on Friday comes as top diplomats from the two countries try to revive a cancelled summit between Trump and Kim, which was due to be held in Singapore on June 12.
Kim Yong-chol was greeted by White House Chief of Staff John Kelly before heading, along with several other officials, towards the Oval Office entrance.
He arrived in the US capital from New York, where he held talks with US Secretary of State Mike Pompeo on Wednesday and Thursday.
Pompeo was also seen inside the Oval Office on Friday.
Considered the North Korean leader’s right-hand man, Kim Yong-chol is the most senior official from Pyongyang to visit the US in 18 years.
He is the vice chairman of the central committee of the Workers’ Party of Korea.
The last time a North Korean official visited the White House was in 2000, when then-Vice Marshal Jo Yong-rok met President Bill Clinton and US Secretary of State Madeleine Albright.
Following his meeting with Kim Yong-chol on Thursday, Pompeo said that talks on the summit “are moving in the right direction”, but added that a Trump-Kim summit will only take place if there’s substantial agreement on denuclearisation.
Both the US and North Korea have committed themselves to the “denuclearisation” of the Korean Peninsula, but it is far from clear how that can be achieved.
Al Jazeera’s Kimberly Halkett, reporting from the White House, said that the two sides are still “very far apart” when it comes to the pace of the denuclearisation.
But Halkett also quoted White House officials as saying that Trump is “personally invested” in the talks scheduled on June 12.
Disputes between Washington and Pyongyang led Trump to cancel the June 12 meeting – only to see a flurry of diplomatic efforts surrounding the proposed summit in recent days.
Even as the Singapore summit remains unclear, the head of the US delegation involved with the preparation of talks with North Korea, said on Friday that the discussion is “moving in the right direction”.
“As both President Trump and Secretary Pompeo indicated, there’s much work left before the proposed summit,” Sung Kim, who also serves as the US ambassador to the Philippines, was quoted by South Korea’s Yonhap news agency as saying.
“We believe that we’re moving in the right direction to the ongoing series of consultations, including Secretary Pompeo’s engagement with Vice Chairman Kim Yong-chol … our discussions at Panmunjom and of course the discussions in Singapore, as well,” he added.
Sung Kim made the remarks during his visit with South Korean Foreign Minister Kang Kyung-wha on Friday.
Sung Kim’s delegation has been in talks with North Korea officials, led by Vice Foreign Minister Choe Son-hui at the demilitarised zone of Panmunjom on Sunday and Wednesday.