Abstract: Aim To study the synthetic procedure, properties and flame retardant efficiency of a novel halogenated phosphate. Methods The obtained phosphate was used to treat flexible polyurethane foam(FPUF), and the flame retardant and physicomechanical performances of FPUF were measured to evaluate the phosphate's efficiency. Results and Conclusion When the loading of the flame retardant is 12%-15% of polyether, the LOI of FPUF is increased to 23 5%-25 5% from 17 5%, and the horizontal burning rate is decreased by 68%. But the elongation and the rebound degree of FPUF are cut down by about 10%. While the tensile strength remains unchanged basically.