The Children's Museum inside the National Museum of Korea in Yongsan, Seoul has different entry rules from the main permanent galleries. Admission is free, but visitors must book online; same-day ticket issuance at the entrance is not available. Mobile tickets are checked at entry.
When to book: Individual reservations open 14 days before the visit at 00:00. You can reserve up to five tickets in one transaction, and the limit is one visit per person per day across personal and group bookings. Children under 36 months still need a ticket, and children must enter with an adult guardian. If your plan changes, cancel before the reserved session begins.
Late arrival and no-show: An online reservation is automatically cancelled if its holder does not enter within 30 minutes of the session starting. Under the museum's published policy, failing to arrive by that point without cancelling the reservation results in a 60-day restriction on Children's Museum visits from the no-show date, with other reservations during that period also cancelled. The system allowing remaining-seat reservations up to 50 minutes after a session begins does not mean an existing reservation can arrive that late.
Groups are different: Qualified school or childcare organizations must use the group tab, with separate participant limits, weekday rules, documentation and no-show penalties. Do not apply the personal 60-day penalty to group reservations automatically.
Review current conditions on the museum's official Children's Museum reservation page or call 02-2077-9647. The general museum's free permanent galleries and paid special exhibitions follow different admission requirements.