〔Abstract〕 Objective To investigate the theoretical basis and new treatment methods of specific anti-Porphyromonas gingivalis yolk antibody liposome(anti-Pg-IgY liposome) in clinical adjuvant treatment of chronic periodontitis and improve its efficacy by observing its entrapment efficiency and the effect of in vitro sustained release. Methods Anti-Pg-IgY liposomes were prepared by thin film dispersion method. Zeta potential and particle size of anti-Pg-IgY liposomes were determined by dynamic light scattering particle size distribution instrument. Entrapment efficiency was determined by dialysis method combined with Elisa.In vitrorelease rate of anti-Pg-IgY liposomes in 0.9% physiological saline was investigated, and its quality was evaluated by transmission electron microscope. Results The Zeta potential of liposome was(-38.55±0.16)mV, the average particle size was(82.48±2.3) nm, the polydispersity index was(0.313±0.01), the entrapment efficiency of liposome was 40%, the cumulative release rate in 0.9% physiological saline was less than 20% within 4 h, about 50% within 24 h, and the release rate in 108 hours was 79.9%. Conclusion Anti-Pg-IgY liposome has high entrapment efficiency,nanometer size and good stability. It is expected to realize long-cycle sustained release in periodontal pocket.