DWAYNE “The Rock” Johnson plays a tough guy in the movies, but in real life he’s a big softie with a HUGE heart!

And to thank his mom Ata for everything she’s done to help him become so suc­cessful, Dwayne gave her a brand-new white Cadillac SUV for Christmas.

He shared the special event with fans on his Face­book page recently, posting photos of his emotional mother as she set eyes on the luxury car for the first time.

“At 14, I saw my mom crying about our only car being repossessed,” Dwayne wrote. “This felt good. Merry Christmas, Mom.”

The 6-foot-5 former wres­tler has also been generous with his alma mater, the Uni­versity of Miami. He donated $2 million to the school’s Newman Alumni Center and another $1 million to help renovate the school’s football facilities. It’s the university athletics department’s largest alumni donation in history.

And he can certainly afford it – his estimated net worth is a whopping $70 million.

Dwayne and his ex-wife Dany – who share custody of their 11-year-old daughter, Simone – also founded The Rock Foundation, which funds a number of programs for underprivileged, at-risk youth, as well as children suffering from illnesses or disabilities.

“Dwayne has a heart of gold and he lives his life like that every day,” a fam­ily friend praised. “He has definitely done his mama proud.”