Abstract: To investigate the optimal process of ultrasound-assisted preparation of chitooligosaccharide-stabilized Pickering emulsion and its stability performance, chitooligosaccharide and pectin were used as Pickering particle raw materials and sunflower oil as the oil phase, and emulsification activity index (EAI) and emulsion stability index (ESI) were selected as the indexes, the process conditions of ultrasound-assisted preparation of chitooligosaccharide-pectin stabilized Pickering emulsions were optimized by single factor experiment and response surfaces methodology, and the stability of the emulsions prepared under optimization was investigated. The results showed that the optimum conditions for chitooligosaccharide-pectin stabilized Pickering emulsion were as follow: Mass ratio of chitosan and pectin was 0.05, solution pH was 5.22, oil phase volume fraction was 32%, and ultrasonic power was 350 W. The EAI and ESI of emulsions reached (5.129±0.003) m²/g and (796.68±4.43) min respectively at the optimal condition. The stability experiments and the observation of the internal microstructure of the emulsions showed that the emulsions had excellent emulsification stability at 25~50 ℃ and 0~100 mmol/L salt ion (NaCl). Therefore, the novel Pickering emulsion optimized by ultrasound tech-nology improved the emulsification characteristics of the emulsion, which provided a reference for the preparation of chitooligosaccharide Pickering particles and their applications.