He replaces Greg Barclay who will remain on the Board as an independent director, having stood down in to his recent appointment as Chairman of the International Cricket Council.
Rugby League has been a central part of his entire life as a ball-boy, player, junior coach, referee and League administrator.
Speaking on his appointment Grant said he felt proud and privileged to become the Chair of International Rugby League, especially as the fraternity looked forward to the excitement of the World Cup later in the year.
Meantime, the Rugby League World Cup is taking place between October 23 and November 27.
It is the pinnacle of international Rugby League, globally contested every four years.
The three tournaments, men’s, women’s and wheelchair competition, will take place in 21 venues across 18 host towns and cities in England.