Pickering stabilizers exhibit unique interfacial properties; however, only limited types of these particles are available for the food industry. Therefore, the main aim of this study was to develop a food-grade Pickering stabilizer using a protein isolate obtained from the protein-rich lupin variety AluProt-CGNA® (LPIA). Lupin protein aggregate particles (LP-APs), obtained from LPIA, were produced through a facile and scalable technology based on heat-induced particle formation. LP-APs with high surface charge and partial wettability were effective for stabilizing O/W emulsions. These emulsions were prepared by using high-speed homogenization with LP-APs dispersions. The creaming index, microstructure and physicochemical properties of Pickering emulsions were investigated. The results showed that LP-APs exhibit great potential to perform as stabilizers for O/W Pickering emulsions (O/W). Additionally, LP-APs exhibited much better interfacial and emulsifying properties than did the unheated LPIA. Heating greatly improved the emulsification performance of protein particles, especially at high concentrations (>3%, w/v). The formed emulsions were highly stable against creaming upon storage over 14 days. These findings are of great importance for the formulation of LP-APs-based emulsions with improved properties (e.g., stable against creaming and coalescence) and will also significantly extend the application of lupin proteins in the food industry.