The intestinal microbiome in horses consists of numerous microorganisms, including bacteria, fungi and protozoa. It plays a key role in maintaining the proper health of these animals. Modern research on the horse microbiome reveals its significant impact on the digestive process, metabolism, immune system and mental state of animals. The microbiome of horses is particularly interesting because of their herbivore and unique digestive system, which requires cooperation with microorganisms in the process of decomposition of plant fiber and energy production. Understanding the role of the microbiome in the context of horse health is of great importance for improving treatment methods and nutrition management, as well as for better understanding the mechanisms of gastrointestinal diseases. The purpose of this article is to present an overview of current scientific research on the intestinal microbiome of horses and its impact on health.