Antibacterial action of pure and Fe-modified titanium dioxide samples was tested using Escherichia coli ATCC 25922. The bacterial growth was examined in the presence of a synthesized preparations – in dark and with UV light. The photodisinfection activity was assessed by plotting of survival curves and calculation of removal efficiency. In order to estimate the post-irradiation effect, the behavior of the bacterial suspension in presence of each photocatalyst after 24 h dark period was tested.