Polydopamine eugenol microcapsules (PDA@EO) with controllable size were prepared by emulsion template interfacial polymerization using eugenol (EO) as the core material and dopamine (DA) as the shell material. The chemical structure, morphology, size and its distribution, and properties of the microcapsules were characterized by FTIR, TG, UV-Vis, SEM and TEM. The results showed that the microcapsules had regular spherical shape with size ranging from 55 to 94 nm. The encapsulation efficiency and the encapsulation capacity ware 25.35% and 0.6288 g/g, respectively. The cumulative release rate reached 68.39% after 24 h. The excellent adhesive property of PDA@EO microcapsules on different surfaces was verified by a comparative study. When treated with common bacteria in the site of oral infection Staphylococcus aureus (S·aure) and Escherichia coli (E·coli) for 24 hours, the growth of the cells was inhibited, PDA@EO Compared with free eugenol, the antibacterial activity of microcapsules increased by 36.84% and 35.52%, respectively; when the concentration of the microcapsule reached 2.0 g/L, the antibacterial activity of PDA@EO microcapsules against both bacteria was more than 99%.