A device for treating wounds using a vacuum and having a gas-tight wound-covering element, which, when placed in contact with the body of the patient, forms a wound space between the respective wound and the wound-covering element. The device includes an absorption body, which is a layer, enclosed in an envelope, of a textile section, interspersed with super-absorbing particles. The liquid-permeable envelope has pores, the size of which does not exceed that of the super-absorbing particles. The absorption body, inserted in the wound space, has an initial volume, which enlarges in the course of the absorption process, and a final volume, so that, due to the size of the pores of the envelope, the absorbed wound secretions remain within the absorption body and, with that, below the wound-covering element, until the absorption body is removed from the wound space.