"SriLankan Airlines looks forward to a fruitful long-term relationship with Etihad,"Sri Lankan chief executive Manoj Gunawardena said.
"I have no doubt that the new agreement will be of significant benefit to our passengers throughout Europe and Asia, including Sri Lanka."
The two airlines had been code-sharing the Abu Dhabi-Colombo sector since September 2007.
"Etihad’s codeshare with SriLankan Airlines has worked well during the last year and we are pleased to extend the deal and provide our customers with flights to the Maldives which we expect will be hugely popular with our holidaymakers," Etihad chief executive James Hogan said in a statement.
SriLankan operated a number of code-shares with Emirates, a shareholder who was managing partner of the airline until March 2008.
Codesharing allows passengers of one airline to book flights on the other. Passengers then have an increased number of destinations to fly to while an