Scouten's family said he died Wednesday at Inova Fairfax Hospital of complications from hip surgery, The Washington Post reported.
During almost a half century in presidential service, Scouten gained a reputation for discretion. He once told The New York Times he did not tell his wife everything he saw at the White House.
He was in the Oval Office in 1963 when he learned President John F. Kennedy had been shot in Dallas, and he remained in the White House for five days. He was with first lady Nancy Reagan when she was told in 1981 her husband, President Ronald Reagan, had been shot.
"Everyone teases me about it to this day, but I admired Rex Scouten so much that when I received a wonderful Cavalier King Charles Spaniel for Christmas in 1985, I named him 'Rex' as a tribute to him," Nancy Reagan said Friday.
Scouten, a Michigan native, served in the Army in World War II and was wounded in Italy. He joined the Secret Service after graduating from Michigan State University in 1948 with a degree in criminal justice.
He joined the White House staff as assistant to the chief usher in 1957 and remained there until the Clinton administration, except for a brief period under President Lyndon Johnson when he served as White House liaison for the National Park Service.
Scouten was chief usher from 1969 to 1986 and then White House curator until his retirement in 1997.
As chief usher, Scouten's responsibilities included supervising White House redecoration for new administrations and arrangements for state dinners.