Two-component polyurethane flame-retardant coatings were prepared by blending phosphorus-containing modified polyesters (PCMs) and polyisocyanate. PCMPs were synthesized by polycondensation of dimethyl phenylphosphate, a flame-retardant component, with 1, 4-butanediol, adipic acid, and trimethylolpropane. The content of dimethyl phenylphosphate was varied in 10, 15, and 20 wt% for the reaction. These new flame-retardant coatings showed various properties comparable to other non-flame-retardant coatings. Coatings with 20 wt% dimethyl phenvlphosphate did not burn using the vertical burning test.