Abstract: To improve the nutrient content and storage stability of chicken soup, in this study, the process parameters of ultrasonic pretreatment-assisted chicken soup preparation were optimized using the response surface method, and the effects of ultrasonic pretreatment on nutrient migration and micro-nano particles (MNPs) formation during stewing were investigated. Results showed that, the optimum conditions for ultrasonic pretreatment of chicken soup were temperature 50 ℃, time 20 min, power 830 W. Under these conditions, the contents of solids, protein, amino acid nitrogen, total sugar, and total lipid in chicken broth increased by 35.13%, 26.09%, 33.47%, 21.59% and 44.04%, respectively. During MNPs formation, particle size and polydispersity index decreased to 322.27 nm and 0.47, respectively, and the absolute value of the Zeta potential increased significantly (P<0.05). In addition, ultrasonic pretreatment induced changes in the protein secondary structure of MNPs, reducing α-helices and converting to β-folding and protein solubility to 87.40%, thereby improving chicken soup stability. These results demonstrate the potential application of ultrasonic pretreatment technology in producing high-quality chicken soup.