This work sought to explore a new method for using corn silk polysaccharide (CSP) and peanut protein isolate (PPI) to stabilize high internal phase emulsions (HIPEs). An ultrasound-assisted hydrothermal technique was used to make the PPI-CSP covalent complexes and HIPEs. Particle size analysis, rheological studies, and multiple light scattering techniques were used to analyze the stability and attributes of the emulsion. Microscopic studies reveal that the PPI-CSP complex encapsulates oil droplets at the interface, forming a typical oil-in-water (O/W) emulsion. The stability of the HIPEs is notably improved by the inclusion of CSP; the smallest particle size was recorded at a 2:1 PPI to CSP ratio (12.91 ± 0.13 μm). According to rheological evaluations, all HIPEs behave in a shear-thinning manner and have solid-like properties. Furthermore, this emulsion exhibits excellent stability during thermal treatment, changes in ion concentration, different pH values, and storage.