"I feel wonderful!" the 37-year-old actress and mother of six told Us Weekly at the premiere.
"I’m very very grateful for all the support, it means a lot to me," Jolie, wearing a custom-made Saint Laurent gown, told reporters.
"I do not feel any less of a woman," Jolie wrote in her May 14 piece for the Times. "I feel empowered that I made a strong choice that in no way diminishes my femininity."
Jolie said that she had decided to undergo the procedure to minimize her 87 percent breast cancer risk.
"What you guys are seeing is just absolutely who she is and how she has always been," Pitt told Metro UK.
"Faced with a problem she’s going to face it head on and find out what her options are and going to make a smart decision for her and share that knowledge with whomever will listen," he said.