Aim - to evaluate the effect of exogenous serotonin on the motility of the bauhinian valve and to identify the mechanism of this effect. Materials and methods. The experiments were performed on 36 Wistar rats weighing 250-270 g. The motor function of the ileum, ileocecal region, and caecum was recorded in the animals of two experimental groups (n=30). tonic contractions and propulsive activity. As a result of the study, it was shown that serotonin has a prokinetic effect on the ileum, the ileocecal junction with the Bauhinian valve and the caecum. 5HT3,4 receptors are located on the cytolemma of intramural serotonergic neurons and EC cells, and 5HT1,2 receptors are located on the cytolemma of effector smooth muscle cells. The Bauhinian valve contains the largest number of 5HT3,4 serotonin receptors, which is due to the complex function of this formation in the regulation of propulsive activity at the border of the small and large intestine.