To develop stable polysaccharide-based emulsions, many studies have focused on the interfacial behavior of adsorbed polysaccharides. This review first discussed the mechanism of polysaccharides self-assembly at the oil-water interface. It can be concluded that polysaccharides can form a thick and strong interfacial membrane that stabilizes emulsions through steric hindrance and electrostatic interactions. In particular, we also investigated the influence of various conditions (i.e., mechanical stress, heating, pH, enzymatic treatment, and ionic strength) on the architecture and properties of polysaccharide-based emulsions. Additionally, the interactions of polysaccharides with other molecules in the emulsion system were summarized, revealing that co-adsorption further changes their properties. Furthermore, current approaches for monitoring the behavior of adsorbed polysaccharides at the oil/water interface were reviewed, highlighting their advantages and limitations. Lastly, we emphasized the potential of polysaccharides for producing environmental-friendly emulsions in the food industry.