West Ham were beaten 4-1 by Liverpool on Saturday and the board have dismissed Bilic this morning.
“West Ham United can confirm that Slaven Bilic has today left his position with the club,” a club statement read.
“The Chairmen and board of West Ham United would like to place on record their thanks and gratitude to Slaven and his team for their services over the past two-and-a-half years, but believe a change is now necessary in order for the Club to move forward positively and in line with their ambition.
“West Ham United can confirm that Bilic’s coaching assistants Nikola Jurcevic, Edin Terzic, Julian Dicks and Miljenko Rak have also left the Club with immediate effect.
“The club’s search for a new manager to take West Ham United forward is underway and an announcement regarding Bilic’s successor is expected to be made over the coming days.”
Moyes is set to take over until the summer.
West Ham sit third bottom in the Premier League with nine points from 11 games.
They have won just twice this season and are sliding towards the Championship.
Bilic was out of contract in the summer and he was called into the training ground for talks this morning.
Karren Brady was seen departing just minutes ago after Bilic was told of the decision.
Moyes left Sunderland in the summer and has since been linked with the Scotland post although admitted he was keen to return to club football over the weekend.
Moyes said yesterday: “I’m interested, yes, but at the moment it’s not available.
“I’ve been there myself and I know what Slaven’s going through. He must be hating it and wanting to get a result as quickly as he can.
“For me to go back in it means a manager has lost his job and I wouldn’t wish that on anybody.
“I’ve always said I wanted to go back into club management. If the right opportunity comes around then I’ll be interested.”
West Ham have been preparing for Bilic’s exit for some time, with results failing to improve.
They also spoke to Ronald Koeman, sacked by Everton two weeks ago, and to Guus Hiddink about taking over as caretaker manager, as well as former Watford manager Walter Mazzari.
Moyes though is regarded a safe pair of hands who can work on a tight budget.
West Ham have also considered former Manchester City manager Roberto Mancini, currently in charge at Zenit St Petersburg, as a possible long-term option, as well as Hoffenheim coach Julian Nagelsmann, and Manuel Pellegrini, another former City manager now in charge at Chinese Super League club Hebel China Fortune.
But Moyes is set to get the job and wants Phil Neville as his assistant.