Jesse Marsch was sacked as Leeds manager on Monday after the American failed to halt the struggling club's slide towards the Premier League relegation zone.
Leeds' 1-0 loss at Nottingham Forest on Sunday left them just one place above the bottom three after seven league games without a win.
"Leeds United can confirm head coach Jesse Marsch has been relieved of his duties," said a statement on the club's Twitter account.
Leeds last won in the Premier League on November 5, a dismal run that prompted Leeds fans to call for Marsch to be sacked after the Forest defeat.
They got their wish just 24 hours later, with the 49-year-old relieved of his duties after only a year in charge at Elland Road.
"Jesse joined the club in February 2022 and was instrumental in keeping the club in the Premier League on the final day of last season," the statement said.
It added: "The process of appointing a new head coach is under way and we will continue to keep supporters up to date throughout the coming days."
Former Leipzig coach Marsch, who was hired on a three-year contract to replace the sacked Marcelo Bielsa at Leeds, departs with his 17th-placed side out of the relegation zone only on goal difference.
Former Aston Villa boss Steven Gerrard, West Brom manager Carlos Corberan and ex-Tottenham coach Mauricio Pochettino have all been linked with the Leeds job. (AFP)