Exclusive Details

The Rock says his mom, Ata Maivia-Johnson and his cousin were struck HEAD ON by a drunk driver this week ... and luckily, they survived.

Dwayne Johnson's uncle Afa tells us Ata and Lina Fanene were driving home from a fundraiser their family runs every year -- the Usos Foundation Banquet -- when they were crashed into by the alleged drunk driver.

Both women were rushed to a local hospital and we're told Ata was hospitalized for 3 nights. Afa wouldn't say what injuries the 65-year-old sustained ... but he did tell us it was a very scary scene.

The Rock posted a picture of the crash and his mom's white Escalade -- the one he bought her for Christmas in 2012 -- clearly totaled. Same goes for the other car involved.

Fanene -- who currently works for WWE's NXT division -- posted a photo of the actor/wrestler visiting her in the hospital.

Ata and Lina also posed for a pic in the SUV on August 2nd on their way to the fundraiser.