The charity will open its first upmarket, designer outlet at Westbourne Grove in London this week and then plans to roll the new format out across the country.
Apparel in the stores will include a mix of newly produced clothing, remade and donated fashions. Designers from the London College of Fashion will be involved in the production of clothing for the outlets.
Oxfam head of retail Sarah Farquhar told the Financial Times: Our challenge was to shake up some of the traditional stereotypical images of charity shops. What had become apparent, particularly in urban larger centres, was that we needed to specialise and to do it with a bit more authority.
The move has been given greater weight by the current, uncertain economic situation that has led to a donation drop-off.
We see people hanging on to what they have got although we do pick up customers because people look to maintain their lifestyles on a restricted budget, she added.
Oxfam has brought in former Topshop brand director Jane Shepherdson to oversee the new format. Well-know designers including Giles Deacon and Christopher Kane have donated used garments and will create exclusive pieces for the charity to auction on Ebay.