The 58-year-old had an expiring contract with the Brussels giants, and opted not to extend his stay with the Belgian champions.
"I have made the decision to move on. It's in the club's best interest to end our collaboration. We looked at all the pros and cons, and the best thing to do is go our separate ways," Jacobs stated at a press conference.
Jacobs took charge of Anderlecht during the 2007-08 campaign, and has since guided them to two league titles and one Belgian cup.
"I have never worked with a coach like Ariel, and that's probably one of the main reasons why he stayed here such a long time. It's a real shame to see him go," commented club president Roger Vanden Stock.