Wallis will join the womenswear fashion chain, which is part of the Mosaic group, from lingerie retailer Ann Summers, where he has been retail and property director for the last four years.
Oasis managing director Sharon O’Connor said: “The scope of the role is new for the business. Ian will lead retail operations both in the UK, Ireland and internationally. It is a significant appointment to a new senior management team at Oasis.”
Wallis' start date has yet to be confirmed.
Oasis has around 300 stores and concessions.