The 39-year old Sibley, who will move from his existing role as Octagon CSI's head of cricket and rugby in early May, will replace the current incumbent Terry Blake who recently announced his retirement.
The acquisition of Sibley is something of a coup for the ECB and will aid the governing body significantly as it looks to recoup the financial arrears it suffered during this year's Cricket World Cup.
Commented Tim Lamb, chief executive of the ECB: "I have no doubt that Mark will prove to be a very valuable addition to the ECB's executive team. He brings a wealth of experience that will be crucial in ensuring that the ECB maximises all its existing commercial opportunities, and identifies new ones.
"It's essential that the ECB continues to build on its commercial activities and thereby provides a solid financial foundation for the whole game - Mark will play the leading role in doing this."
Octagon's Mark Sibley has moved to take up the position of commercial director at the England and Wales Cricket Board.
