The paper should contribute to the knowledge of the warp knitting structure possibility to change its dimensions. The ability of knitted fabrics to be deformed has been well known and used for example for simplification of the garment construction. In this case it is not necessary to keep the shape of the parts of garment so strictly as when using woven fabrics. The problem of flat textiles deformability has grown more important in the age of technical textiles and composites. For example, to transform flat textile product (so called 21) textiles) into shaped (3D) composite with textile reinforcement is impossible without change of the fabric dimensions and space. It is possible either through yarn or fibres axes deformation (extension) or using the possibility of knitted structure to be prolonged even without change of the yarn length. This possibility is enabled and achieved mainly by the thread to thread slippage in the basic structural elements - loops or, more preciously, in the yarn crossings (bounding points). The change 2D-3D is often very complicated and needs combination of biaxial and shear deformation. The behaviour of the knitted structure is a little special and untypical. When the matter such as steel is submitted to one axes stress, the prolongation of one dimension is higher then the reduction of perpendicular dimensions and so the volume or space is increasing. The knitted fabric can often in the case alike reduce its space in a drastic way, because the prolongation in one direction can cause much greater contraction in the cross direction. One can find a lot of fields of fabric use when the deformation plays an important role (sometimes positive, sometimes negative). By change we can name vain implants, compressive stockings, geotextiles etc.