"2 Days 1 Night Season 4" had a guest appearance by Hyeri from Girl's Day on the 12th episode, which aired on KBS.

Hyeri was confirmed as one of the visitors before to the cast's departure on their gastronomic adventure in Mokpo, South Korea. Those who had never met her before were a bit taken aback, but Moon Se Yoon, who had previously worked with her on tvN's "Amazing Saturday," suggested that they "match our energies a little, should we?" "This is my first time ever on '2 Days 1 Night' in my whole life," Hyeri explained. Kim Jong Min remarked, "It's like if we had brought a rambunctious young kid to play."

Ms. Moon Se Yoon stated that Hyeri was exceptionally good at eating and added, "She eats in such a pleasant and joyful manner that it awakens one's hunger." Moon Se Yoon inquired of Ravi about his relationship with Hyeri, to which he said, "We're friends." You might not be aware of it, but in the entertainment sector there is a 'Hyeri' line." On being asked who the other members of the "Hye" line were, Hyeri responded, "It's only Ravi and Hanhae." "It's a nice, comfortable line." When given the opportunity to choose teams, Hyeri chose Moon Se Yoon.

The first stop for the cast and guests was to have jjolboktang (small puffer fish stew), which is a Mokpo specialty. "I'm fascinated, but what do the other teams do?" Hyeri inquired of the production crew after learning that only one team was permitted to eat. "Do they just sit there and watch?" Hyeri was given the opportunity to taste only one ladle of the soup, and she ended up shooting a one-spoon mukbang as a result of this decision (eating broadcast). "Can you tell me what it tastes like?" Ravi inquired. Why aren't you providing an explanation? When we complete the taste test, we discuss how it tastes with one another. The fact that you're not saying anything is driving me insane!"

"Wow," Hyeri said. It has a highly delicious and deep flavor, to describe it briefly. Seokbakji [kimchi prepared from big chunks of radish] would be a wonderful accompaniment." "I don't eat anything if it doesn't taste delicious," she continued. If it doesn't taste nice, I'll tell you immediately away. My instructions were to the authors were that they should only make the greatest meals."

With Hyeri, the cast participated in a variety of activities such as peeling layers off a balloon, in which Hyeri became quite competitive despite the cast members' attempts to provide her with advice on this and that. She also participated in the "omegi tteok" game, which is a hallmark game of the "2 Days 1 Night Season 4" series, and they afterwards performed a kkakdugi jegichagi dance routine (hacky sack).