Pardew was sacked this morning after a meeting with new Chairman Eggert Magnusson and the majority shareholder Bjorgolfur Gudmundsson.
West Ham have lost 11 of their 17 games in the Premiership this season and have struggled to recreate the kind of form which saw them go within a minute of winning the FA Cup final last season.
The full statement from the official site reads:
West Ham United have today announced the departure from the Club of Alan Pardew.
Alan has made an important contribution since joining as manager in September 2003 but this season's results have been disappointing and have left the Club in a very difficult position.
The Chairman, Mr Eggert Magnusson, and the Board have been concerned by the performances of recent weeks and feel that it is the right time to make a change in the best interests of the Club.
Mr Magnusson and the Board would like to place on the record their thanks to Alan Pardew for his hard work and commitment and to wish him well for the future.
The search for a successor is now underway in order that a new manager can be in place ahead of the January transfer window.
First Team Coach Kevin Keen will take temporary charge of team affairs until a new appointment has been made. No further statements on this matter will be made by the Club before that time.