The relevance of the study is conditioned upon the fact that outbreaks of anthrax are periodically recorded on the territory of Ukraine, not only in ruminants, but also in pigs, fur animals, dogs, and people. The purpose of the study is to investigate the protective properties of the experimental vaccines and the abacillary vaccine “Antracol” and to prove the immunogenic effect of the extracellular toxin from the B. anthracis K-79 Z strain. Cultures of vaccine strains of anthrax were used for the experiments: B. anthracis 55, B. anthracis SB, B. anthracis K-79 Z and the “Antracol” vaccine (experimental development). Microbiological, clinical-biological, and biotechnological research methods were used in the study. The protective effect was investigated on guinea pigs (Cavia porcellus). An acute experiment was performed with a virulent strain B. anthracis 92 Z. Exotoxin was obtained from the specified cultures. The titre of the exotoxin was found in the disk precipitation reaction. The highest result regarding exotoxin production was recorded in B. anthracis K-79 Z 1 : 128 with a total protein concentration of 0.19 mg/ml, while the exotoxin of B. anthracis strain 55 with a titre of 1 : 32 showed a high total protein concentration of 0.4 mg/ml. The effect of B. anthracis exotoxins on the body was investigated by administering them to laboratory animals in different titres of exotoxins, followed by infection with the pathogenic strain B. anthracis 92 Z. The exotoxin of the vaccine strain B. anthracis K-79 Z in a titre of 1 : 64-1 : 128 shows the best protective properties against the pathogenic strain. It was found that the vaccine strains of B. anthracis SB and B. anthracis K-79 Z have the same level of protection of laboratory animals during experimental infection, which is 60%, while the vaccine from the strain B. anthracis 34F2 showed a level of protection of 20%. Based on the results of the study, it was found appropriate to use exotoxin B. anthracis in the development of prophylactic preparations against anthrax. The research results can be used by scientists and specialists in the field of veterinary medicine to develop new and improve the available vaccines for effective anthrax prevention