Vieira had been appointed coach in July last year on a three-year deal after the former France international left his role at Crystal Palace.
Strasbourg finished 13th in the league in his first season in charge but the club thanked Vieira for bringing through youth talents in a season of transition.
"We would like to express our gratitude and thank Patrick for the work he has accomplished during this first phase of the project and we wish him much success in the future," club president Marc Keller said in a statement.
"He will always be welcome at the club."
Last year, Strasbourg were taken over by BlueCo after the consortium which purchased English Premier League club Chelsea reached an agreement to become shareholders of the French side.
The club said a new coach will be appointed soon. The new Ligue 1 season kicks off on the weekend of August 17-18.
