A shipbuilding company based in Port Macquarie has won a contract with the US Army worth more than $250 million.

Birdon will build up to three hundred and seventy four 'Bridge Erection Boats', designed to help the army cross large bodies of water.

The boats are used to help the army erect temporary bridges in warzones.

Managing Director Jamie Bruce said they were picked over some of the largest shipbuilding companies in the world.

"Both large and small contractors, and we certainly had quite a few challenges along the way, particularly up against some of the larger defence contractors," he said.

"They have not made it easy for us, but I think ultimately it came down to our design."

Birdon Managing Director Jamie Bruce said this could lead to more work in future.

"This particular boat itself is used by the majority of militaries around the world, and the majority of those vessels are quite old, so we expect to see quite a few opportunities in other parts of the world for this boat," he said.

"Particularly now the US military has the product."