Katherine Whitton, global chief marketing officer at Specsavers, is leaving the business in April.
The company said that Whitton, who will have been at the opticians brand for three years by the time she departs, is making the move to return to the UK from Guernsey, where the role is based.
A member of Campaign's Power 100, Whitton has overseen the restructure of Specsavers' in-house creative agency, which includes hiring Nicola Wardell from Havas London to head Specsavers Creative.
Whitton has also developed a new brand strategy and store format during her time at Specsavers.
The company credits her with "successfully navigating the brand through the ongoing Covid-19 crisis" by changing the ways in which Specsavers engages with customers to help them continue receiving sight and hearing care.
John Perkins, chief executive of Specsavers, said: "Katherine has been a truly valued member of our board, supporting the growth of our business and strengthening our brand and marketing capabilities.
"In particular, her help in shaping our response to the pandemic has been invaluable. Her customer-centric approach has helped us reposition the brand and expertise we deliver in sight and hearing care every day."
The company is seeking a replacement.
Whitton took over from brand director Richard Holmes, who retired after 11 years in 2018. Before this, she worked at Barclays for eight years. She has also held roles at American Express and British Airways.
Whitton said: "I have absolutely loved my time at Specsavers. It's been a real privilege to be trusted to guide the development of this iconic brand and the marketing agenda. I've had the pleasure of working with so many committed, compassionate and talented people in our stores and support offices around the world."