An Albion statement read: "Gary Megson today informed the board of West Bromwich Albion by letter that he wishes to leave the club at the end of his current contract in approximately eight months' time on 30th June 2005.
"The club accepts this letter as a resignation and the board believes it is now in the best interests of West Bromwich Albion that Gary Megson no longer remains in charge of team affairs. As such, he has been relieved of his duties while contractual matters are resolved.
"This is a crucial period for the club and the board regards the timing and manner of Gary Megson's announcement as extremely unhelpful, particularly following the team's disappointing performance at Crystal Palace on Saturday.
"Nevertheless, the board intends to move swiftly to appoint a new manager who will be fully focused on the job of taking the club forward in the Premiership. Until such time, Frank Burrows will act as caretaker-manager.
"The board would like to acknowledge Gary Megson's major contribution during his term as manager and wishes him well in the future."
Assistant manager Frank Burrows has been put in temporary charge of first team affairs while the search for a new boss begins.