The aim of the present study was to increase the decomposition rate of raw feather waste by choosing keratinolytic fungi of soil origin. The experiment was carried out in laboratory conditions on mineral-keratin medium (ground feathers) in three-weeks' old fungi cultures. Feathers were used as the only source of C, N and energy. The following parameters were taken into account while selecting the optimum conditions for fungi keratinolysis: various quantities of raw feathers, mineral salts (phosphates, magnesium, calcium, iron and zinc salts), pH, temperature, type of inoculum. Keratinolytic fungi activity was evaluated on the basis of: percentage decrease of substrate mass, release of peptide substances, additional N-aminic and N-ammonic release. The optimised substrate medium of (in g dcm^–3): K₂HPO₄ – 0.5; MgSO₄•7H₂O – 0.025; CaCl₂•7H₂O – 0.025; FeSO₄•7H₂O – 0.015; ZnSO₄•7H₂O – 0.005; chicken feathers – 10.0; pH 6.5-6.8. The optimum incubation temperature was established within the range 20 to 25°C. The best inoculation material was a suspension of spores (106 cm^–3 g^–10 of feathers). The optimum fungi breeding time was 21 days. Application of the optimum decomposition parameters of raw feather waste by fungi, shortened the process by 20-30%. It represented about an 80% loss of substrate mass in three weeks of fungi breeding. Phosphates and magnesium ions belonged to those parameters which hastened the above process most when 1% of substrate was applied – (3 and 10 times the increase in concentration, respectively).