The process of making carbon active non-wovens can generally be reduced to the following stages: 1. the selection of fibres of the properties favourable for the raw material intended for adsorptive material, 2. making a non-woven precursor of the raw material selected, 3. subjecting the non-woven precursor to a carbonization process, 4. the process of activation of the carbon nonwoven. Viscose fibres are characterized by large surface development and a certain porosity of their own. These properties are considered to be very favourable for the raw material intended for adsorptive material. Taking the above into account, precursor non-wovens were produced from viscose fibres. The investigations aimed at obtaining a non-woven precursor of a possibly large mass density with the simultaneous preservation of the present value of air-permeability [1]. Precursor non-wovens were made by means of needle-punching. The carbonization process of precursor non-wovens was carried out with the preservation of constant parameters. The part of investigations being presented concerns the effect of technological parameters of making precursor non-wovens on the properties of the resultant carbon non-wovens. Special attention has been paid to the relationship between the fabric density and the air-permeability of non-wovens.