Singapore Airlines and Emirates - which owns a third stake and manages SriLankan - had already said they would only fly during daytime to Katunayake following Tamil Tiger air raids at a nearby air base and Colombo.
Cathay Pacific has suspended flights to the country.
Sri Lankan said it was already contacting passengers traveling in the next 48 hours and asked them to contact the airline on 0197335500 for more information.
The Tamil Tigers use several light aircraft to slip into the South of the country from unknown locations in the north to drop improvised bombs.
Government officials have said they intend to stop night flights at the international airport by May 10 as a pr