Simmons, 50, replaces the outgoing Mick Potter, who leaves Knowsley Road to join Bradford for 2011.
Saints Chairman Eamonn McManus stated: “Royce will bring vast experience to the Saints. He is as used to successfully coaching elite players and developing young talent alike.”
He said: “This is a huge honour for me and a challenge that I am ready for. St. Helens are one of the great historic names in world rugby league and are at the crossroads for a great future as they move to a new stadium with a squad that has a great balance and blend of proven internationals and some of the brightest young prospects in the
“I’m fully aware of their record of achievement and the style of rugby which has so distinguished them over the years. I’m really looking forward to taking up the role moving to England.”
Simmons will be joined on the coaching team by current club captain Keiron Cunningham, who will assist the academy and also with fitness and conditioning.