The Seagulls, who became Women's Premier League champions on Sunday, have met the necessary WSL licensing requirements.
The Sussex side beat Sporting Club Albion 4-2 in Sunday's play-off and will take their place in WSL 2 in spring 2017.
Brighton lost just two games as they won the Southern Division this season.
The WSL's on- and off-field criteria included finance and business management, facilities and marketing requirements.
"Brighton thoroughly deserve their promotion after such a fantastic season and for their development off the pitch in recent years," the Football Association's head of leagues and competitions Katie Brazier said.
"It is great for the league that we now have a club on the south coast, which will help us to develop a wider fan-base."
Brighton chief executive Paul Barber added: "We are very proud of the achievements of our women's team this season.
"The club's initial ambition has been to reach the Women's Super League and, having achieved that aim, we are now very much looking forward to kicking off the new season in 2017."
Brighton & Hove Albion Women have had their promotion to Women's Super League Two approved.