Here is a list of countries with direct flights to Jeju Island (CJU), South Korea : Taiwan (Taipei), Japan (Osaka), China (Beijing, Shanghai), Singapore,Vietnam.
For more detailed information about direct flights to Jeju from overseas countries and flight schedules, please visit https://www.airport.co.kr/jejueng/index.do#slide1.
Alternatively, you can search for direct flight information using the image below.