The Hammers announced the news on Saturday morning, two days before their Premier League clash away at Everton on Monday night.
“The club can confirm that assistant coach Bruno Saltor, first team coaches Billy Reid and Narcis Pelach, lead goalkeeper coach Casper Ankergren, and goalkeeper coach Linus Kandolin have also left with immediate effect.
“The board would like to thank Graham and his coaching staff for their hard work during their time with the Hammers and wish them every success for the future.
“The process of appointing a replacement is underway. The club will be making no further comment at this time.”
Potter was appointed in January after Julen Lopetegui and led the east Londoners to a 14th-place finish.
There was the expectation that results would improve this season, but four defeats in their opening five Premier League games piled the pressure on Potter.
The Hammers also suffered a Carabao Cup second-round elimination at the hands of Wolverhampton Wanderers under the former Brighton & Hove Albion and Chelsea boss.
Fans have actively voiced their displeasure with recent results, and there are reports that a swift replacement could be appointed.
Various reports have said that former Nottingham Forest and Wolves manager Nuno Espirito Santo could be in the hotseat as soon as Monday.
