Traditional polymer anti fouling materials mostly come from petrochemical resources, which are non renewable and environmentally friendly. Research on renewable, widely sourced, and low-cost plant oils waterborne polyurethane has been extensive. There are many researches, but the development difficulty is relatively high, and it is not widely used. Therefore, the development of high-value plant oils materials has important practical significance. In this paper, polyethylene glycol monomethyl ether (MPEG) with different molecular was coupled to the side chains of plant oil fatty acids by epoxy ring opening reaction of soybean oil. The ring opening efficiency and structure reaction products were characterized by FT-IR, GPC, and 1H-NMR, and the hydroxyl value was determined by standard titration method. The optimal ring opening process for MPEG epoxidized soybean oil was determined, the mole ratio of hydroxyl to epoxy groups was 1.5:1, and after dropping ESO, the reaction continued for 15 min. The hydroxyl value range of the obtained vegetable oil-based anti fouling polyol is 77.17~120.20 mg KOH/g. Series of anti-fouling waterborne polyurethane coatings synthesized from the obtained plant oil-based antifouling polyol were simply prepared by introducing polyurethane structure. The results show that the coating has good antifouling performance for Gram-positive and Gram-negative bacterial strains, as well as bacteria that are easy to form biofilms. The successful preparation of these polyols from plant oil is of great significance for the high-value utilization of biomass resources.