He has also been nominated as ArcelorMittal's Executive Vice President.
Simon is the Chief Commercial Officer of ArcelorMittal Mining and a member of the Group Management Committee.
"Simon Wandke has been nominated Executive Vice President of ArcelorMittal and promoted to Chief Executive Officer of ArcelorMittal Mining, with immediate effect," the steel maker said in a statement today.
ArcelorMittal's Chairman and CEO Lakshmi Mittal said that Simon has proved a strong operator since he joined the group in 2011 and was a clear choice to take up the position of CEO.
ArcelorMittal is the world's leading steel and mining company, with a presence in 60 countries and an industrial footprint in 19 countries.
In 2014, ArcelorMittal had revenues of USD 79.3 billion and crude steel production of 93.1 million tonnes, while own iron ore production reached 63.9 million tonnes.