Julia Roberts is actually not a Roberts, here's what her real biological surname is!

Julia Roberts is not Roberts. The secret was even big news for the 'Ticker to Paradiseactress herself. The Oscar winner recently appeared on Henry Louis Gates, Jr.'s show 'Finding Your Roots,'where she learned the shocking family secret.

In the recent episode, Jr. said that she has been using the wrong surname all her life. As he went on to explain her family tree, Gates revealed that her correct surnameis Mitchell, not Roberts.

In the show, Gates told the Oscar-winning star that the man, Willis Roberts, whom she thought was her great-great-grandfather, actually died more than a decade before her great-grandfather John was even born.

In the 1850s, Rhoda got married to Willis R. Roberts, who passed away in 1964, "over a decade before" she gave birth to Julia's great-grandfather, John Pendleton Roberts, in 1878.

Shockingly reacting to this, Julia said, "Oh, wait—bbut am I not a Roberts?"

Later, Gates went on to explain that after he did some research andfound "a cluster of matches" that connected the 55-year-old actress to a man named Henry McDonald Mitchell Jr.

So, basically, his biological great-great-grandfather was Mitchell, not Roberts.

"So we're Mitchell's?" amused Roberts.

"You're Julia Mitchell," Gates Jr. told the actress before adding, "You are not a Roberts, biologically."

Further, the historian revealed that Mitchell was married and had six children at the time of his affair with Roberts' great-great-grandmother Rhoda and lived a few houses away from her great-great grandmother's home.