Potassium lithum niobate (KLN; K3Li2Nb5O15) thin films were prepared by an rf-magnetron sputtering technique using a sintered K- and Li-excessed target. In this experiment the optimum sputtering conditions were an rf power of 100 W, working pressure of 150 mTorr, and substrate temperature of 600°C. When the KLN was grown on a Corning 1737 glass substrate at a temperature of 600°C with a sputtering pressure range of 50–200 mTorr, the thin film KLN was (001) oriented. The (001) preferred orientation of a KLN thin film is due to the minimum surface energy of the (001) plane. The lattice constant of an as-grown thin film has a slightly larger value than the tetragonal tungsten bronze structure range. The lattice constant and full width half maximum (FWHM) of the thermal-treated films were shrunk by the stress relaxation of the thin film. When annealing at a temperature of 650°C the value of the lattice constant of the c-axis was in the middle of the tetragonal structure range. Accordingly, the use of a K- and Li-enriched sintered KLN target enables the fabrication of c-axis-oriented ferroelectrics directly onto an amorphous substrate.