At Seoul National University's Gwanak campus, President Yoon Suk-yeol's alma mater, pro and anti-impeachment rallies were held simultaneously on the morning of the 17th. The number of participants in both rallies exceeded 200 at one point, following the previous gathering on the 15th. They faced each other from a distance of 50 meters, using loudspeakers to criticize one another. Some students noted, "(The noise) interferes with studying." The pro and anti-impeachment rallies dispersed around 2 p.m.
Earlier, 'Seoul National University students defending liberal democracy' announced that they would hold an 'anti-impeachment declaration' at the 'Acropolis Square' in front of the student center at 11:30 a.m. on the same day. In response, a group called 'Seoul National University Collective Action,' composed of the Seoul National University Democratic Alumni Association and the Korean University Students Progress Alliance, held a 'counter-rally' calling for the impeachment of President Yoon at the same location an hour earlier.
Participants in the impeachment advocacy rally, which gathered first, held up signs reading, "Immediately resign Yoon Suk-yeol, the instigator of insurrection," and "How could we endorse a coup? Let's protect democracy," while chanting slogans such as "Impeach Yoon Suk-yeol" and "Arrest Kim Keon-hee." Around 11 a.m., participants in the anti-impeachment rally began to assemble, waving the South Korean and U.S. flags while shouting, "Arrest Lee Jae-myung" and "Investigate election fraud." Both rallies also saw participation from individuals not associated with the university. The number of participants at the start was less than 100, but it gradually increased to over 200 at one point.
The pro and anti-impeachment sides faced each other, shouting, "Get lost, pink XX!" and "The forces endorsing insurrection should step back." As tensions rose between the sides and some participants began to engage in physical confrontations by grabbing each other, police intervened. This conflict persisted from the 15th into this day, prompting some students to express discomfort. The rally took place in front of the central library.
Kim Mo (28), a graduate student at Seoul National University, said during an afternoon meeting on the same day, "I come to the library regardless of weekends or weekdays, but the noise from the pro and anti-impeachment rallies interferes with my studying," adding, "While it's fine to argue passionately, I hope it doesn't disturb other students."
That day, some departments at Seoul National University held orientation for new students. Choi Mo (19), a new student who came with parents, remarked, "I was a bit surprised to see outsiders participating in rallies on campus," and expressed a hope that "this conflict would be somewhat resolved when the semester begins."