This paper aims to prepare oregano oil microcapsules and improve the stability of the oil. The microcapsule was prepared by complex coacervation using gelatin and Arabic gum as wall material and the process conditions were optimized by the single factor experiment and the orthogonal experiment, and the antibacterial effect of the microcapsule was tested. Results showed that the optimal conditions were as follows: the ratio of core and wall was 3:1, dosage of the emulsifier was 0.1%, cutting 2 min at speed 6000 r/min, pH value 4.5; curing time 60 min at temperature 55 ℃ and shaking speed 250 r/min. Under these conditions, the encapsulation efficiency could reach 83.1%. In conclusion, oregano essential oil by microcapsule can significantly increase the persistence of antibacterial effect.