The Gospel singer - who performed at the I Will Always Love You hitmaker's funeral in February - will release The Whitney I Knew on 31 July, with the book including never before seen photographs of the pop superstar.
Whitney - who had a history of substance abuse problems - was found dead in the bath of her Beverly Hills hotel room in February and BeBe has promised to use the book to reveal "heartbreaking accounts that led to her ultimate defeat".
It was recently confirmed that Whitney's mother Cissy Houston will release a book about her daughter next February.
She has signed a multi-million dollar deal to write with "candor, honesty and respect" about her daughter, who died as a result of accidental drowning and effects of heart disease and cocaine use in February.
'Deeper understanding'
Gospel singer Cissy said: "When I lost my daughter Nippy (the nickname Whitney's family gave her), the world lost one of the most beautiful voices and an extraordinarily beautiful and charitable woman.
"In sharing our story in this book, I hope to give her fans something to treasure, the way we all treasured Whitney. We are still receiving thousands of letters each day from her fans, and I hope reading this book will provide a deeper understanding into my daughter's true story."
Whitney famously spiralled into drug addiction alongside her husband Bobby Brown - the father of her 19-year-old daughter Bobbi Kristina - in the 90s and Cissy will address these issues in her book.