Basically, antibiotic resistance develops due to the incorrect use of antibiotics in various branches of animal husbandry, both during the treatment or prevention of diseases, and due to their long-term use as growth stimulants. As a result, costs for the treatment of farm animals and companion animals are increasing. Antibiotic resistance among microorganisms is a threat to every person, every patient, medical and veterinary worker. Also, this is a big challenge for the field of health care, veterinary medicine and agriculture as a whole. It is very difficult to solve the problem of resistance, because it is not one-sided. Medicines that were effective a few years ago are losing their positions today, and their use is being forced to be limited. According to data from the World Health Organization, the rapid increase in the resistance of microorganisms to antibacterial drugs threatens the scientific gains made by scientists during the last 50-70 years. The formation of antibiotic resistance is due to the genetic properties of microorganisms, as a result of their acquisition of new genetic information, or due to a change in the level of expression of the bacterial cell's own genes. An important factor in the fight against the spread of antibiotic resistance is the pharmacodynamic substantiation of the dosing regimens of antibacterial drugs and their use for specific microorganisms.There are guiding documents that control and recommend the reliability of determining the sensitivity of microorganisms to antibiotics, in particular - methodological recommendations of the European organization EUCAST, the data and material of which are periodically (annually) updated. These documents are developed primarily for routine use in clinical laboratories that do not cover technical procedures for identifying resistance mechanisms at the molecular level. However, a significant part of the given data, research on determining the sensitivity of microorganisms to antibiotics, is performed in national reference laboratories. There is a change in the sensitivity of the micro-flora to antibiotics, which is not covered by the screening of multi-resistant microorganisms, or the direct detection of resistance in clinical samples. Therefore, the study of the problem remains relevant and expedient. Key words: microorganisms, resistance, antibiotics, gram-positive bacteria, gram-negative bacteria, control, disease, spread, problem, treatment, animals.