Cardiff City are looking for their third new manager in six months after owner Vincent Tan decided not to offer Sabri Lamouchi a new contract.
The 51-year-old joined on a short-term deal in January and ensured the club avoided relegation to League One.
Lamouchi had been open to staying on with chairman Mehmet Dalman saying he had been optimistic the Frenchman would remain in charge.
"I would like to thank everyone at the club," Lamouchi said on Instagram.
"It has been an honour to be entrusted with this brief mission, and to have successfully fulfilled it. The players fought their best to keep the club at this level, and I hope this will be a starting point for next season.
"While our paths may diverge, I feel grateful for the opportunity that was given to me and wish everyone the very best in the future. To the fans, thank you for your support everywhere we played, it meant a lot to me."
A Cardiff City statement read: "We can confirm Sabri Lamouchi will depart at the conclusion of his current deal.
"Sabri joined the Bluebirds at the end of January 2023, overseeing 18 fixtures, and winning six matches.
"Cardiff City would like to thank Sabri for his efforts and contribution in helping us secure our place in the Championship for 2023-24 and wish him all the very best for the future.
"The board of directors at Cardiff City FC have already begun the process of appointing a new management team."
It will mean a fourth manager in the space of a year for the Bluebirds, who began last season with Steve Morison in charge before Mark Hudson took over in September.
With the team winless in 11 games and one point above the relegation places, Cardiff brought in former Nottingham Forest boss Lamouchi with the aim of staying up.
The Frenchman oversaw six wins in 18 games to keep Cardiff in the second tier and he had said he was ready for talks about leading the side into the new campaign.
Initial discussions with Dalman took place before meetings with the club's Malaysian owner who had the final say on a decision which ended Lamouchi's time in south Wales.