The Ministry of Transport and Civil Aviation said in an advertisement in state-run The Sunday Observer newspaper that long term lease options were available for investors.
The airport had been designated as a bonded area and free trade zone.
The airport will have a fully open skies policy with all freedoms of the air indicating that foreign airlines will be able operate to third countries and to domestic airports from the airport.
Expressions for interest will close on August 12, 2016.
The Chinese designed and built airport Mattala Rajapaksa International Airport, has made large losses and has been unable to service loans, becoming a drag on Airport and Aviation Services (Sri Lanka) Ltd, the state airport company.
Government officials have been trying to persuade Chinese firms to take the airport and run it.