3,4-Di-(2'-hydroxyethoxy)-4'-nitrostilbene (2) was prepared and condensed with 2,4-toluenediisocyanate and 3.3'-dimethoxy-4.4'-biphenylenediisocyanate to yield polyurethanes 3 and 4 containing the NLO-chromophore dioxynitrostilbenyl group. Polymers 3-4 were soluble in common organic solvents. Polymers 3-4 showed a thermal stability up to 300 degreesC in TGA thermograms with T-g values in the range of 109-114 degreesC in DSC thermograms. The SHG coefficients (d(33)) of poled polymer films were around 3.2 x 10(-9) esu.