The new resort, to be built near the airport 50 kilometres (31 miles) west of Seoul, would feature facilities such as a hotel, casinos, convention centres, shopping malls and hospitals, she said. "We plan to develop the property like the resorts in Las Vegas or Macau," she said, adding negotiations to select a developer are underway.
The airport already earns 65 % of its revenue from hotels, duty-free sales and other services not directly linked to flying. Spending by Chinese and Japanese account for more than a quarter of duty-free sales.
The airport earned us$ 1.26 billion in duty-free sales from January to October last year, and says it beat Dubai International Airport to become the world's top airport in such sales during the period.
South Korea's biggest hub handled about 35 million passengers last year and has been several times been rated the world's best airport by the Airports Council International.
Incheon is also considering a bid for Edinburgh Airport, whose operator was ordered by antitrust regulators to hive off Scotland's largest gateway.
"We are internally reviewing whether or not to join the bid as part of our overseas business drive," the spokeswoman said.
The conservative government announced a plan in 2008 to sell up to a 49 % stake in Incheon airport as part of a privatisation drive. But a parliamentary bill has been stalled in the face of opposition from lawmakers and civic groups.