Boasting more than twelve full-size pitches, a sports science centre, two hotels and a conference auditorium, the impressive venue will be used by the England squad to train for their World Cup qualifying matches.
The royal couple will be taken on an exclusive tour around the grounds with England manager Roy Hodgson, as well as watching the England squad's first training session at the park.
William will later give a speech at the conference auditorium, and join a reception at which he and Kate will be the guests of honour.
FA chairman David Bernstein expressed his delight at the couple's appearance.
He said: “The opening of St George's Park is truly a momentous occasion in the history of The FA."
“Next year we will celebrate The FA's 150th anniversary, and this moment will be recorded as significant as any that has gone before us in the last 149 years."
“We are particularly delighted that both the Duke and Duchess can join us to open this facility.”
The couple's sporting venture is just one of many this year. William an Kate were seen enjoying a series of Olympic and Paralympic events this summer.