Warnock was widely tipped to step down as Leeds boss at the end of the current campaign, but admitted in his post-match interview that it may be better for the club if they appointed an interim manager for the remaining six Championship games.
Neil Redfearn will take control of the first team until a permanent replacement is chosen.
"We would like to thank Neil for his efforts during his time as our manager and share his disappointment that we could not achieve promotion this season," Chief Executive Shaun Harvey told the club's official website.
"We now need to look to the future and the search for his replacement is underway, for which there is no fixed timescale as securing the services of the right person is the primary objective, so as to give us the best chance of promotion next season.
Leeds have not won in their last six Championship games and now sit 12th in the table.