Applied to oil-based alkyd paint, the performance of the paint film remains unchanged and even some indicators are improved after introducing an appropriate amount of water into the paint, ultimately achieving the effect of reducing costs and VOC. Different from the interface dispersion of ordinary water additives or surfactants, polysaccharide resin achieves true oil in water effect by completely encapsulating water molecules in the resin through hydrogen bonding between molecules, resulting in better storage stability and more ideal construction effect. In addition, polysaccharide resin itself is a film-forming substance, and after adding water, it still maintains its original luster, dryness, covering power and other indicators without decreasing. Polysaccharide resin can be used to produce high flash point products, low VOC products, improve safety and save transportation costs.