Abstract: Milk and dairy products serve as crucial sources of nutrition for humans, and their composition is extensively researched. Milk exosomes are nanoscale phospholipid bilayer vesicles released from the milk source and present in the extracellular environment, which contain protein, lipid, and genetic material, among other cell-specific substances. Milk exosomes distinguish themselves from other types of exosomes in that they are rich in sources and readily producible on a large scale. They can be selectively absorbed by target cells to exert physiological effects and thereby influence various physiological and pathological processes. Milk exosomes directly participate in and regulate diverse physiological processes by carrying their endogenous bioactive molecules including proteins, microRNAs, and lipids, manifesting significant biological activity, likewise act as ideal carriers of active substances due to their outstanding biocompatibility and high loading capacity, rendering them suitable for drug delivery and transportation. Hence, this article summarizes the effects of endogenous active substances and the role of milk exosomes as signal transduction carriers, and reviews the latest research progress in regulating intestinal health, so as to facilitate in-depth research and extensive application of milk exosomes in domains such as food science, nutrition, and medicine.