The 57-year-old told an audience in New York on Friday it would start "from [his] first memory" and "hopefully... go all the way up to the Super Bowl" half-time performance he gave in 2007.
The book is tentatively titled The Beautiful Ones, after a track from Prince's 1984 Purple Rain album.
Publisher Spiegel & Grau said it would "take readers on an unconventional and poetic journey" through Prince's life.
The publishing house, an imprint of Random House, said the memoir would include stories about Prince's music, "the family that shaped him and the people, places and ideas that fired his creative imagination."
"The good people of Random House have made me an offer that I can't refuse," Prince is reported by the New York Times to have said.
The singer said he was working on the book with his "brother Dan" - a reference to Dan Piepenbring, web editor of The Paris Review.
"He's a good critic and that's what I need," Prince continued on Friday. "He's not a 'yes man' at all and he's really helping me get through this."
"We're thrilled to be publishing Prince's powerful reflections on his own life in his own incandescently vivid, witty and poetic voice," said Chris Jackson, Spiegel & Grau's executive editor.