The 27-year-old made 20 appearances for Albion last season but found himself surplus to requirements this term and had a spell on loan with Gillingham.
Boss Gus Poyet told the club website: "We thank Romain for his contribution to the club throughout his time at Brighton.
"He helped the side in many different positions last year but with the players we brought in over the summer he knew that his chances would be limited this season.
"We were honest with him and he was a great professional around the club and on the training ground.
"We wish him all the best of luck for the rest of his career."
Youngster Matt McGiveron has also had his contract terminated by mutual consent.
- Sports & Recreation