Ms Fewster will run the company’s Western Australian operations – which includes various state and community newspapers, radio stations and Channel 7 Perth – effective immediately.
She joined the company in April 2017 from iiNet with more than a decade of management and executive experience.
Adam Everett, Seven West’s current general manager – circulation & distribution, has been promoted to COO.
The company announced Mr Driscoll’s decision to step down from his role as CEO after 5pm on Friday, citing family reasons.
Mr Driscoll was in the role for less than a year, joining from marketing firm MarketForce in September 2017.
He replaced Chris Wharton who moved into retirement in March 2017 after taking extended leave in 2016.