In the study, the evaluation of organic waste biodegradation with the addition of a biopreparation containing proteolytic, lipolytic and cellulolytic bacteria strains was carried out. The efficiency of the biopreparation was evaluated in a half-technical scale within 3 months of composting and was based on an analysis of protein, fat, carbohydrates content and general bacteria count. The experiment showed that introduction of the biopreparation caused high development of proteolytic, lipolytic and cellulolytic bacteria (early) in the first month of composting. The process was accompanied by a considerable organic compound reduction, especially in proteins and carbohydrates rate. In relation to indigenous microflora, the introduced biopreparation speeded up the process of organic compound mineralization over twicely. A 58% reduction of organic matter was obtained after 3 months.