Formerly the trust's deputy chief executive, chief nurse and chief operating officer, Bennett succeeds Prof Joe Rafferty, who retires after 12 years in the role.
Bennett said: ‘I look forward to working with the talented staff at Mersey Care and our system partners to continue to improve health and ensure high quality care for all of our communities across the Cheshire and Merseyside region.'
She has had a breadth of experience within the NHS, starting her career as a nurse, she has progressed through various leadership roles within the North West in both provider settings and at NHS England.
In addition, Bennett has held a variety of roles since joining Mersey Care in 2016, and her appointment was ratified by the trust's Council of Governors.