The league said he died unexpectedly and did not give a cause.
Madden led the then-Oakland Raiders to their first Super Bowl victory in 1977 and became a hugely popular television analyst after retiring from coaching.
He later became the face of Madden NFL Football, one of the most successful sports video games ever.
"Nobody loved football more than Coach," NFL commissioner Roger Goodell said in a statement.
"There will never be another John Madden, and we will forever be indebted to him for all he did to make football and the NFL what it is today."
