The 37-year-old mother of six has explained her reasons for having the surgery in the New York Times, reports the BBC.
She said her doctors estimated she had an 87% risk of breast cancer and a 50% risk of ovarian cancer. "I decided to be proactive and to minimise the risk as much I could," she wrote.
She said the process began in February and was completed by the end of April.
In an article entitled My Medical Choice, Ms Jolie explained that her mother fought cancer for nearly a decade and died at the age of 56.
She said she had sought to reassure her children that the same illness would not take her away from them, "but the truth is I carry a 'faulty' gene, BRCA1, which sharply increases my risk of developing breast cancer and ovarian cancer".
She said that once she "knew that this was my reality", she had taken the decision to undergo the nine weeks of complex surgery required for a double mastectomy.
Her chances of developing breast cancer have now dropped from 87% to under 5%, she said.
She praised her partner, Brad Pitt, for his love and support throughout the procedure, and said she was reassured that her children had found nothing in the results "that makes them uncomfortable".
"I feel empowered that I made a strong choice that in no way diminishes my femininity," she said.
"For any woman reading this, I hope it helps you to know you have options," Ms Jolie went on to say.
"I want to encourage every woman, especially if you have a family history of breast or ovarian cancer, to seek out the information and medical experts who can help you through this aspect of your life, and to make your own informed choices."
The award-winning actress and director is also a long-time supporter of humanitarian causes. She is currently a UN special envoy.
During the period she was undergoing the double mastectomy procedure, Ms Jolie visited the Democratic Republic of Congo with UK Foreign Secretary William Hague – and attended the G8 summit of foreign ministers in London – to raise awareness over sexual violence in conflict.
She also helped launch a charity to fund girls' education set up by the Pakistani schoolgirl activist Malala Yousafzai who was shot by the Taliban last October.
Ms Jolie has three biological children and three adopted children with Brad Pitt.