"This new agreement will increase both choice and convenience for customers," Oman Air’s Chief Executive Officer, Wayne Pearce said in a statement.
"It allows Oman Air’s customers to book with us to fly to Singapore and increases available connections from Colombo to Male."
Oman Air operates Airbus A330s and Boeing B737s on the routes while SriLankan Airlines operates Airbus A320, A330 and A340 aircraft out of Colombo to Male and Singapore.
"The present partnership further strengthens the longstanding cooperation between two airlines and will serve to boost tourism and trade between the two countries," SriLankan chief executive Kapila Chandrasena said.