Öz Barley roots were traeted for 1-24 hours vith 0.1-10 mMol/1 lead uitrate Solutions and examined by transmission eîectron ınicroscope. Lead deposits were observed in the middle lamella, celi walls and in the pinocytctically formed vesicle at the firs^ and third hours, at low conccntrations. The plasmalertıma acts as a barrier to the influx of lead intc the protoplasm. But this was not considered as a complete protection mechanism. With iucreasing concentra- tîons and time, lead has migrated to the cytopîasm, and even to the nucleus and the nucleolus. The epidermal and the cortical cells were highly susceptible to the lead. They were sericusiy injured exhibiting plasmolysis and disorganized celi structure. The endodermis has protected the Central cyîinder for a short time. The eîectron micropgraphs made after 6 and 24 hours of lead treatments in the ali experimental combinations have shown dense lead deposits in ali tissues. Lead has been taken up and has accumulated by barley rocts and caused structural damages in root cells.