Well-crystallized Y-type hexagonal ferrite films with highly c-axis orientation were successfully preparated on Ag substrates by polymerized complex method. The Co-2-Y phase started to form at 780 degrees C and nearly single-phase Of Co-2-Y was formed when the films heat-treated above 820 degrees C. The films had large in-plane magnetic anisotropy with small in-plane Hc of about 300 Oe. When it was heat-treated at 860 degrees C, the Ms had maximam value of 192 emu/cm(3). The heat-treatment time also influence the magnetic properties of the films. The films with nearly the single-phase Of Co-2-Y were formed when the films had stoichiometric Ba:Co:Fe ratio of 1:1:6.