Smith made news in March when he wrote an Op-ed piece that ran in The New York Times and condemned the loss of "moral fiber" at the investment bank.
He had been an executive director at Goldman and his letter marked his last day there after nearly 12 years.
Grand Central announced Wednesday that Smith's "Why I Left Goldman Sachs: A Wall Street Story" will come out Oct. 22.
A Grand Central spokesman declined to comment on reports that Smith's deal was worth $1.5 million.
The publisher said the book will be a call for "genuine financial reform."