Adams is a hugely popular figure in Britain who has won pretty much every major title open to her as an amateur.
"I want to take women's boxing to the next level, become a world champion and do great things," the bubbly flyweight said on Monday, announcing she was turning professional.
"It's going to be quite different: no headgear for one. I have to create my own team now, but I'm really excited about doing that."
Adams, a hugely popular figure in Britain who has won pretty much every major title open to her as an amateur, signed a long-term promotional deal with Frank Warren and will make her professional debut at Manchester Arena against an as-yet-unnamed opponent.
She is also scheduled for a "homecoming" fight at Leeds on May 13.
Warren, who sat alongside Adams as the announcement was made at BT Tower in London, said: "I've not been the greatest advocate of women's boxing. My head's been turned.
"I've had to eat humble pie, and thought, 'Are you a dinosaur?'"
Rob McCracken, performance director of GB Boxing, said Adams left Britain's successful Olympic boxing programme with his blessing.
"Nicola has made a huge contribution to both the Olympic programme and the sport of boxing," he said.
"She has won everything there is to win and her place in history is secured as the first woman to ever win a gold medal for boxing and then top it by winning a second one in Rio."
Adams follows fellow London gold medallists Ireland's Katie Taylor and Claressa Shields of the United States in spending the rest of her career as a purely professional boxer.
Although professionals are now allowed to compete at the Olympics, Adams has likely ended her hopes of winning a third gold medal because GB Boxing have made it clear they will favour fighters who are members of their programme.
Adams was the first female fighter to represent England in 2007 and, after overcoming a career-threatening back injury, became boxing's first Olympic women's gold medallist when she defeated China's Ren Cancan in the flyweight final at London 2012.
Adams became the first female boxer to retain an Olympic title when she did so at last summer's Rio Games.
Having previously won European and Commonwealth gold medals, 2016 also saw Adams complete a clean sweep of major titles when she won her first world championship by defeating Thailand's Peamwilai Laopeam in Kazakhstan.