"I wanted Bill to remain as our Chairman during this important period of transition for the Club and I am delighted that he has accepted my request to do so," Moshiri said in a statement on Friday.
"Bill's knowledge and vast experience will be crucial for us as we look to reset, deliver on external investment and position Everton for a successful future."
Colin Chong, who is the chief stadium development officer focusing on the delivery of the new Everton Stadium at Bramley-Moore Dock, has been appointed interim CEO and director.
Director of finance James Maryniak will take over all finance matters as interim CFO. Chartered accountant John Spellman is also joining the board.
The personnel changes come on the heels of the recent departures from the board of chief executive Denise Barrett-Baxendale, finance officer Grant Ingles and non-executive director Graeme Sharp.
Their departures signalled the beginning of major changes at the Merseyside club, amid ongoing investment talks with U.S. group MSP Sports Capital to support the completion of the new stadium.