Maude Ballou worked as King's secretary from 1955 to 1960, when King led the Montgomery Improvement Association and the Southern Christian Leadership Conference.
Ballou, who turned 88 Friday, is selling the items October 17 in New York through Texas-based Heritage Auctions.
People can bid in person or online. Ballou and Heritage Auctions say a portion of the proceeds will be used to establish an education fund at Alabama State University.
"He said, 'Maude, I dreamed last night I died and nobody came to my funeral.' And that was very touching," Ballou said, her chin quivering. "And I said, 'Oh Martin, that's not going to happen. Nothing like that's going to happen to you.'" King was assassinated in 1968 in Memphis, Tennessee.
Some of the more than 100 items are unique, so it's difficult to put a value on them, said Sandra Palomino, director of historical manuscripts for Heritage Auctions. "We're really relying on letting the market decide what the value is going to be," Palomino said.
Another item is a typed final page of King's "I Have a Dream" speech, according to the auction house. The page was sent to Ballou on Jan. 31, 1968, several weeks before King was assassinated, by Lillie Hunter, bookkeeper for the SCLC and secretary to Ralph Abernathy.
Other items include King's handwritten notes for a 1959 speech to inform his congregation that he would be leaving Dexter Avenue Baptist Church in Alabama, where he served as pastor in the 1950s and was involved in the Montgomery bus boycott.
King later moved to Atlanta where he became co-pastor of Ebenezer Baptist Church and continued his work with the SCLC and the struggle for equality.
