Thompson shot himself in 2005 at the age of 67.
The New York Post said Anita Thompson's book "Ancient Gonzo Wisdom" is set for release in February.
The book reportedly will feature the eccentric writer's recollections of some of his assignments, including a discussion he allegedly had with former President Richard Nixon about professional football.
"(It's) the only time in 20 years of listening to the treacherous bastard I knew he wasn't lying," Thompson said of the chat.
Journalist, author and literary critic Christopher Hitchens is writing the introduction for the book, the Post said.
N.J. man wakes up from 10-hour sleep with knife in back
Exploding whale video goes viral on Internet