A filtering bag (3) for a cat litter comprising: an upper part defining an upper edge delimiting an opening of the bag (3) a lower part defining a lower edge where the bag (3) is hermetically sealed, and an intermediate part between the upper part and the lower part provided with perforations intended to filter the litter, the bag (3) being foldable between a screen configuration for filtering the litter through the perforations, and a pocket configuration for transporting the litter hygienically, the bag (3) further comprising a removable hooking means for keeping the bag (3) in the screen configuration.
