Leighton subsidiary John Holland has won a $186 million contract to build the Cape Lambert Port B wharf extension for Rio Tinto in the Pilbara.
The work is part of the mining giant's plans to ramp up Pilbara iron ore capacity to 252 million tonnes a year.
John Holland is already working on the wharf with the new works adding a further two berths.
John Holland executive general manager of energy and resources, Brendan Petersen, said the contract would reinforce the company's presence on major port expansion projects in Queensland and WA and extend John Holland's strong working relationship with Rio Tinto.
"Our project team is currently on site delivering the first stage of the project, so this award builds on this existing work at Cape Lambert and most importantly our ongoing relationship with Rio Tinto," he said.
Leighton shares were off 26 cents, or 1.28 per cent, to $20.10 at 7.55am.