Administrators have been appointed to clothing firms Valleygirl and Temt.
There are about 40 stores throughout the country.
An administrator from Jirsch Sutherland, Stewart Free, said the businesses had suffered due to slow sales and problems securing stock.
He said that had meant difficulties in making payments, especially to landlords.
"We are currently investigating the best options for preserving the business operations, which include investigating a potential sale of the business, and by virtue trying to ensure that employees are best looked after," Mr Free said.
The stores continue to operate in the meantime.