Oxfam Ireland says stock levels in its 49 shops are 'critically low'.
The charity says the volume of donations to its shops has fallen dramatically in the past couple of years.
The recession has meant consumers are buying fewer goods, such as new clothes, meaning they are holding onto their older items for longer and not getting rid of them.
Oxfam says its ability to respond to disasters, such as the Haiti earthquake and Pakistan floods of 2010, is directly related to support for its shops.
