To enhance the added value of silkworm pupae, the composition, structure, and emulsion properties of polysaccharides from silkworm pupae (PSP) were investigated in this study. An analysis of the composition and structure of PSP extracted from silkworm pupae was conducted. High internal phase emulsions (φ=74%) were prepared with the obtained PSP, and the effects of PSP mass concentration on emulsion properties were analyzed by measuring the zeta potential, droplet size, emulsifying activity index (EAI), emulsion stability index (ESI), rheological properties, and storage stability of the emulsions. The results showed that PSP was primarily composed of fucose, galactosamine hydrochloride, rhamnose, arabinose, glucosamine hydrochloride, galactose, glucose, mannose, and glucuronic acid. PSP and its primary components, PSP2 (1.01×106 u) and PSP3 (1.24 ×106 u), were acidic polysaccharides. The mass concentration of PSP significantly influenced emulsion stability. With an increase in PSP mass concentration from 5 to 80 mg•mL-1, EAI increased from 3.43 to 17.24 m2•g-1, ESI improved from 10.39 to 548.30 min, absolute zeta potential rose from 15.77 to 28.10 mV, and droplet size decreased from 135.80 to 62.07 μm. In particular, the emulsion stabilized with 80 mg•mL-1 PSP exhibited the lowest stability index, the highest viscosity, and the best storage stability. The present study demonstrated that PSP consists of natural polysaccharides with excellent emulsifying properties, which can potentially be used to stabilize high internal-phase emulsions. The results of this study can provide a theoretical basis for the development and use of PSP, which has potential for widespread application as a novel green emulsifier and thickener in food processing.