On 9 February 2018, Yo-jong attended the 2018 Winter Olympics opening ceremony in Pyeongchang, South Korea. This was the first time since the Korean War that a member of the ruling Kim dynasty had visited South Korea. She met with South Korean President Moon Jae-in on 10 February and revealed that she was dispatched as a special envoy of Kim Jong-un. She also delivered a personally written letter from Kim to Moon. Kim was later part of her brother's team during the 2018 North Korea–United States Singapore Summit and the 2019 North Korea–United States Hanoi Summit. Her involvement in diplomatic affairs continued as she issued an official statement in March 2020 from her capacity as first deputy department director of the party.