There's no railroad connection between the airport and Jeju City.
Car and bus
Jeju Airport is situated only four kilometers west of the city center. The airport is easily accessible by rental car, via Yongmun Avenue or Gonghang Avenue.
Six buses run from the airport to Jeju City. There's also a shuttle connection (named Limousine) to the major hotels in the city.
Car rental Jeju Airport
You can find counters of car rental companies in the Arrivals Hall of the domestic terminal. Four companies are present, including only one international company, Avis. The other three are local providers: Jeju, Kumho and Daehan.
There are taxis outside the Arrivals Hall. Attention: there are two lines, one for short distances (Jeju City, Aeweol, Hallim, Jocheon, Gimnyeong) and one for long distances (Bukjeju County, Namjeju County, Jungmun, Seogwipo).
There's a large parking lot right outside the terminal. You pay 550 won for the first half hour, and then 300 won per 15 minutes. The maximum day rate is 12000 won (on weekends and public holidays 18000 won). More information about parking at Jeju Airport via +82(0)64 797 2701.