Leighton Holdings subsidiary Thiess has won a $166 million contract to provide earthworks and infrastructure at BHP Billiton Iron Ore's Jimblebar mine near Newman.

Under the contract, Thiess will provide bulk earthworks, drainage and civil structures, road works and buried services.

The contract starts immediately, and the new works are scheduled to be completed by the end of July 2012.

Thiess managing director David Saxelby said the company was "delighted" to continue its relationship with BHP Billiton Iron Ore.

"The project maintains Thiess' long standing presence in the Pilbara region delivering large scale civil projects to blue chip clients," Mr Saxelby said.

Thiess Western Australia/Northern Territory general manager, Ric Buratto, said the company was building on the success of its past contracts and it was well positioned for future civil works contracts in the Pilbara.

Last week BHP announced the Jimblebar mine would be a key plank of its $US7.4 billion Pilbara expansion plans.

BHP committed to spend $US3.4 billion for the development of the Jimblebar iron ore mine and its rail infrastructure, and the acquisition of equipment to deliver initial capacity of 35 mtpa, with the option to expand that capacity to 55 mtpa.