Pardew said: "My record coming to this club has been good, but it's been difficult here. When I arrived they were on the slide and I haven't been able to stop that.
"We're in a sticky situation and I have to accept whatever decision is made."
In a statement on the club's official website, Charlton chairman Richard Murray said: "On reflection of results so far this season, and looking at the future challenges for the remainder of the campaign, it was agreed by both parties that Alan would leave the club with immediate effect."
Assistant boss Phil Parkinson, the former Colchester and Hull manager, has been placed in temporary charge for Tuesday night's Championship trip to QPR.



