Аннотация:We report here on experiments with surface plasmon excitation and propagation along corrugated and smooth aluminum surface in the terahertz frequency range. Plasmon excitation by a picosecond terahertz pulse is shown to be a transient process and plasmon propagation sufficiently changes its measured time profile. Plasmon duration and life-time were defined and plasmon propagation lengths on smooth and corrugated surface were measured. Plasmon propagation length on flat surface turned out to be much smaller than the Drude model predicts.