This follows the appointment of former Liverpool Football Club chief executive Ian Ayre as chair of the board.
Williams' role will include developing the overall commercial strategy for the organisation which is home to BT Convention Centre, Echo Arena, Exhibition Centre Liverpool and ticketing agency TicketQuarter.
Williams joins from the First Direct Arena in Leeds where, as general manager, he led the team that launched the venue four years ago. Prior to this, he was commercial and marketing director at Manchester Arena.
Commenting on his appointment Williams said: "Having worked in the events industry for many years, I am aware of the incredible journey that The ACC Liverpool Group has been on since it opened in 2008. I look forward to bringing my experience of working in large venues and contributing to the continued development of the organisation."
Bob Prattey, chief executive, added: "This is an exciting time for The ACC Liverpool Group with two new senior appointments. Ben brings with him a wealth of industry experience and we have no doubt that he will be an integral part of our organisation across our portfolio of markets – international and national conferences, entertainment and sport, exhibitions and ticketing.
"Next year marks a decade since we opened our doors and we are confident that Ben will be a welcome addition to our talented team."
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