The 33-year-old joined the expansion side from the Montreal Impact prior to the 2018 season, and started all 22 games in which he appeared.
Ciman was LAFC's first captain and scored three goals in the 2018 campaign, helping his side to its current position of third place in the Western Conference.
“Laurent has been a big part of LAFC’s history. He will be forever remembered as the club’s first captain and the first goal scorer at Banc of California Stadium,” LAFC general manager John Thorrington said in a club release.
“These decisions are never easy but we succeeded in finding the right deal for both the club and Laurent. We thank Laurent for his commitment and contribution to LAFC and wish him, his wife Diana, and their family nothing but the best in the next phase of his career.”
Ciman played four seasons in MLS after initially joining Montreal in 2015, and made three All-Star teams while also being named the 2015 MLS Defender of the Year.
The Belgian international was in the final season of his contract, and has opted to return to Europe after previously playing for Charleroi, Club Brugge, Kortrijk and Standard Liege in his native country.