The digestive system of the ruminants possesses anaerobic fungi, which are responsible for the degradation of cellulose and cell wall structures by their enzyme systems. An enzyme complex, bearing cellulase activity from Neocallimastix spp. which belongs to anaerobic rumen fungi, was partially isolated and its effect at various concentrations on bread quality was tested. The addition of enzyme complex into bread dough resulted in a decrease of hardness, gumminess and chewiness, providing a softer crumb, indicating the retardation of the staling in bread, mostly due to the degradation of cell wall components. A professional sensory analysis, carried out by trained panellists indicated that 0.3 mL cellulase containing enzyme solution added was preferred.