Patricio Manuel became the first transgender boxer to fight professionally in the US when he beat Hugo Aguilar at super-featherweight.
The American, 33, won a unanimous points decision at the end of the four-round contest in Indio, California.
There was some booing from the crowd at the end of the fight as Manuel gave an interview.
"I hear some fans aren't happy. It's OK, I'll be back. I'll make them happy then," he said.
Manuel was a five-time national champion in the amateur women's division before taking part in the US women's boxing trials for the 2012 Olympics. He began his transitioning in 2013.
"What's next? I've got some naysayers out there I need to prove that I deserve to be in here," Manuel added.
"I'm not in here for one show, one fight. This is something I love. I'm not done with this sport. I'll be back."