For the first time iridium oxide (IrO2) nanotubes are synthesized by electrodeposition in a polycarbonate (PC) template. Potential cycling (90 cycles) between 0.0 and 0.9 V is used for the preparation of IrOx nanotubes onto the PC template with a pore diameter of 100 nm. Field-emission scanning electron microscopy (FESEM) images show, that IrO2 nanotubes with uniform diameters of 110_10 nm and an estimated length of 1–3 mm are formed. The electrochemical properties and the electrocatalytic activity of a glassy carbon-IrOx nanotube modified electrode toward Cr3+ and As3+ oxidation are investigated. Finally, the modified electrode is used for micromolar detection of the proposed analytes using differential pulse voltammetry.