Do South Korea passport holders need a visa to visit IE?

No visa needed. South Korean ordinary passport holders can enter Ireland visa-free for tourism for up to 90 days. Ireland is not in the Schengen Area, so ETIAS does not apply, and Ireland has no ETA scheme. Republic of Korea is on Ireland's non-visa-required nationalities list. A South Korean ordinary passport holder may travel to Ireland for tourism or a short visit without obtaining a visa in advance, and is normally granted permission to stay for up to 90 days at the port of entry. Ireland sets its own visa policy and is NOT part of the Schengen Area, so the Schengen 90/180 rule and the upcoming EU ETIAS travel authorisation do NOT apply to Ireland — Korean visitors arrive without any electronic travel authorisation. At immigration, an officer decides the length of permission (up to 90 days) based on documents shown, such as a return ticket and proof of funds and accommodation. The passport should be valid for the full duration of the stay (six months' validity beyond the stay is widely recommended). No fee is charged for visa-free short visits. Travellers wishing to work, study long-term, or stay beyond 90 days must apply for the appropriate immigration permission or visa separately.