High‐temperature superconductor GdBa2Cu3O7thin films were growninsituon LaAlO3single‐crystal substrates by dc magnetron sputtering using a single planar target. 93% samples had a zero resistance transition temperatureTc0more than 90 K and a transition width less than 1 K. The best films had aTc0of 92.5 K, a transition width of 0.57 K, and a critical current density of 3.6×106A/cm2at 77 K. The reproducibility is very good. X‐ray diffraction analysis showedcaxis normal to the film’s surface.