Cohen has signed a deal with publisher Henry Holt and Company to share stories from his media career and encounters with celebrities.
The presenter, who also serves as Bravo's executive vice-president of original programming and development, vowed that he will "write every word" of the book, adding: "I don't know how I could settle for anything less than writing it myself."
He added: "I love to write and I'm thrilled that I get to share stories of my improbable intersections with pop culture that have enriched my life."
Cohen's book will be available for purchase next summer.
Last week, Cohen and Today news anchor Natalie Morales were announced as hosts for Miss Universe 2011.
Watch What Happens Live airs Thursdays and Sundays at 11/10c on Bravo.
> Montag upset about Cohen's 'bullying'
Watch Andy Cohen reveal his most embarrassing moment on Watch What Happens Live below (US only):