The 40-year-old Oscar-winning actress adopted Maddox, 13, from an orphanage in western Cambodia in 2002.
She says he will take over the Maddox Jolie-Pitt Foundation, which she set up there 12 years ago "to help local families overcome problems associated with poverty in the region and to help preserve the remarkable habitat and wildlife for future generations," in the future, reported People magazine.
Asked if he would be involved in her upcoming Netflix film, "First they Killed My Father: A Daughter of Cambodia Remembers," about the country's Khmer Rouge communist regime, during which 1.7 million civilians died in the 1970s, the director said, "Maddox will be on set every day after school and involved behind the scenes. And yes, Maddox is already involved in the Foundation and will take over my role when he is older.
"This is the time for our family to understand all that that means to him and to us. My desire to tell this story in the most truthful and accurate way possible will be my tribute to the strength and dignity of all Cambodian people."
Jolie, who has five other children with husband Brad Pitt, still feels a "deep connection" to Cambodia.