Abstract: In this study, Pickering emulsions (PEs) loaded with Mosla chinensis essential oil (EO) were prepared via the nanoprecipitation method using different mass ratios of cellulose nanocrystals (CNCs) and corn starch (CS). The aim was to construct CNC/CS nanocomposite particles, which regulate interfacial properties and enhance the stability and functionality of the Pickering emulsions. First, CNC/CS nanocomposite particles with different mass ratios were prepared and characterized in terms of their structural properties, surface characteristics, thermal stability, rigidity and morphology. Subsequently, the emulsions stabilized by CNC/CS nanocomposite particles were evaluated for droplet size, zeta potential, microstructure, stability, rheological behavior, and both in vitro and simulated gastrointestinal release profiles. The results showed that the incorporation of CNC reduced the particle size of CS from 3682.67 nm to a range of 178.77~441.33 nm, while the absolute value of the zeta potential increased from 7.62 mV to 20.17~45.87 mV, thereby improving dispersion stability. Additionally, CNC improved the interfacial wettability of the composite particles, with contact angles adjusted to between 74.6° and 97.3°, and enhanced their mechanical properties. The emulsions stabilized by CNC/CS nanocomposite particles exhibited excellent physical stability and shear-thinning rheological behavior via a dual stabilization mechanism of interfacial film formation and three-dimensional particle network structure. In vitro release experiments demonstrated that CNC/CS-PE exhibited a slow release of EO, with the release kinetics fitting the Peppas diffusion model. Simulated gastrointestinal digestion results indicated that CNC/CS nanocomposite particles effectively improved the stability of the emulsion and the bioavailability of active components under gastrointestinal conditions. This study provides novel insights and technical support for designing natural polymer-based nanocomposite particles to prepare highly stable and functional emulsions, with promising potential for practical applications.