Abstract: In order to improve the high-value utilization of sunflower seed protein, composite particles were prepared using sunflower seed protein (SSP) and xanthan gum (XG) as raw materials and used to stabilize Pickering emulsions. SSP-XG was characterized using Fourier transform infrared spectroscopy, contact angle measurement, and scanning electron microscopy to investigate the effect of the mass ratio of SSP to XG on the properties of SSP-XG particles; Particle size, Zeta potential, emulsifying activity index (EAI), and emulsion stability index (ESI) as indicators, this study analyzed the effects of different SSP-XG mass ratios and oil phase volume fractions on the microstructure, rheological properties and stability of Pickering emulsions. The results showed that hydrogen bonds, electrostatic interactions, and hydrophobic interactions existed between SSP and XG. The addition of XG made the SSP-XG surface smoother and increased the contact angle measurement value. The SSP to XG mass ratio was 5:1, and the Pickering emulsion with an oil phase volume fraction of 70% had the smallest particle size (6.65 μm), the highest Zeta potential (28.82 mV), and the highest EAI and ESI (1.26 m²/g, 154.81%), the droplets were evenly distributed, presenting a good gel network structure, have good emulsification and stability, and had a lower emulsification index when stored at 4 ℃. They also had high pH stability, ionic stability and heat stability; The shear thinning behavior of rheology indicated that the emulsion was a non-Newtonian fluid; Laser confocal microscopy showed composite particles surrounding oil phase droplets, forming an oil-in-water (O/W) type emulsion. This study provides useful reference for the development of new green food-grade Pickering emulsions.