Two bitumens (BA-1 and BA-2) and their mixts. with a styrene-butadiene-styrene copolymer (HiMA-1 and HiMA-2) were subjected to the aging by the rolling thin film oven test under std. conditions (160 degrees C, 75 min) and at 170 and 180 degrees C for 75, 150 and 225 min. The aging effect were evaluated on the basis of changes in softening point, breaking point, penetration and dynamic viscosity. FTIR anal. was also performed. The aging significantly affected the properties of the BA-1 and BA-2 bitumens but insignificantly of HiMA-1 and HiMA-2 mixts. The increase in the content of carbonyl and sulfoxide groups for unmodified bitumens were obsd. The indices of polybutadiene and polystyrene groups in HiMA-1 and HiMA-2 were not changed during the aging.