BHP awarded the company a number of new contracts in Western Australia.
At Mining Area C in the Pilbara, Mondelphous will upgrade existing conveyer equipment and power switching and stackers.
The company will provide services associated with the demolition and rehabilitation of a number of end-of-life facilities at Nelson Point in Port Hedland.
Both contracts will be completed in the third quarter.
BHP Nickel West has awarded Monadelphous a 12-month extension to an existing contract for the provision of maintenance, shutdowns and off-site repairs at the Kalgoorlie nickel smelter.
Thyssenkrupp Industrial Solutions has also awarded Monadelphous a contract for the construction of a reclaimer and two stackers at BHP's new South Flank iron ore development.
The work will employ 70 people between now and early 2021.
In Queensland, Monadelphous secured a three-year contract from Incitec Pivot for the provision of general mechanical and maintenance services as part of scheduled turnarounds for manufacturing facilities.
Mondalephous has secured an estimated $600 million worth of new mining work since the start of the 2020 financial year.
Shares in the company were down 1.2% to $16.865, about the mid-point of its 52-week trading range.