The former QPR and Leeds United boss was appointed in August following the surprise exit of Tony Pulis.
However, his second stint in charge at Selhurst Park brought only three Premier League wins, with his tenure ending after Friday's comprehensive 3-1 reversal against Southampton.
"Crystal Palace Football Club can today confirm that Neil Warnock has been relieved of his duties and is no longer first-team manager," read a statement on Saturday.
"The club would like to put on record its thanks to Neil for all his hard work and energy over the past four months."
With Palace approaching the halfway mark in the season, they remain a point off safety and without a win in six games.
Sections of the Palace support voiced their discontent at some of Warnock's decisions in the defeat at Selhurst Park on Friday, particularly the substitution of livewire forward Yannick Bolasie.
"You know when you're losing 3-0 and you take Bolasie off, you're going to get stick," said Warnock.
"But you've just got to think about QPR [Palace's next opponents on Sunday] really, so I've no complaints and I have no complaints with them having a go either."
Warnock is the first Premier League boss to depart his position since the start of the campaign, with this season providing the third-longest wait for a managerial change in the top-flight.
The 66-year-old had regularly spoke of his desire to bring in new recruits during the January transfer window, but that responsibility will now fall to someone else.
Keith Millen will again assume temporary control at the club, having previously taken caretaker charge following the departures of Ian Holloway and Pulis.
