Highly transparent conducting Al-doped ZnO films with good adherence and low resistivity have been prepared on polymer substrates by r. f. magnetron sputtering. Mechanically stable polycrystalline conducting ZnO: Al films having a preferred orientation with the (002).planes parallel to the substrates were deposited on polyisocyanate(PI).substrate with resistivities in the range of 4.1×10-3 to 5.110-4 π cm, with carrier densities more than 2.6×1020 cm-3 and Hall mobilities between 5.78 and 13.11 cm2 V-1 s-1. The average transmittance exceeded 80% for a 440 nm thick film deposited on polypropylene adipate (PPA).substrate in the visible spectrum. The quality of obtained films depended on substrate temperatures, sputtering power, Ar pressures and compositions of used targets during film fabrication.