Atar has signed a four-year deal, with the club's president Jean-Pierre Caillot confident that the player will be able to adapt quickly to the French league.
"We are delighted to sign Eliran; he is a star in his country," Caillot told the club's official website.
"For him and his career, he felt it was important to be seen and to be able to play against the bigger clubs in our league.
"It is a new country and a new culture but there is no reason why he cannot adapt to our team and our league."
Atar scored 53 goals in 95 games for Tel Aviv.