UK group Balfour Beatty will electrify the Xinxiang-Heze-Ranzhou-Rizhao railway in China.
The £64m contract has been awarded by the Chinese Ministry of Railways.
The company will deliver an overhead contact line and traction substations for the 616km double-track passenger and freight line.
Work is scheduled to finish in the summer of 2010.
The contract takes the value of the company's recent international rail deals to £188m, Balfour Beatty said.