The Omani group won the contract with a low bid of OR27.2m ($70.65m), beating competition from five other regional and international groups.
Construction of the new airport at Duqm is expected to begin in 2009 and is set to be completed in 2012.
The project will complement a new drydock and ship-building facility currently under construction in the city (MEED 3:7:08).
The Duqm package is the second airport construction contract won by Desert Line in recent months.
The company also won the civil works contract for the new airport at Ras al-Hadd. The company was again the low bidder for that project (MEED 25:3:08).