Synthesis of N-(Substituted)-N'-[5,5'bis(bromomethyl)-2-oxido-1,3,2-dioxaphosphormane-2yl] ureas has been accomplished by condensation of equimolar quantities of chlorides of various carbamidophosphoric acids 3 -with 2,2'-bis(bromomethyl)1,3-propanediol 4 in the presence of triethylamine in dry tetrahydrofuran at 30-40°C. Their structures were established by elemental analyses, IR 1H, C,13, 31PNMR and Mass spectral data.