Co5 Sm/Cr bilayer films were deposited on Si and glass slides by means of a Direct-Current (DC) magnetron sputtering system with substrate heating.Magnetic properties measurements show that the sample with glass substrate has a comparatively large eoercivity (Hc =2 141.2Oe) with a relatively low optimal temperature ( Ta =350 C ).X-ray diffraction patterns indicate that Cr presents a hexagonal-close-packed (hcp) texture on Si,while a body-centered-cubic (bcc) structure on glass substrate,which leads to Co5 Sm films having different lattice constants on Si and glass substrates.At their optimal temperature,the grain size of the sample on glass slide is smaller with its size distribution more uniform.Concurrently,the shape of magnetic domain is more regular and ordered.The value of magnetic switching volume ( V* ) for the film on glass is 1.65 × 10- 18 cm3,smaller than that for films on Si.For the film on glass,the magnetization reversal mechanism is mainly influenced by magnetocrystalline anisotropy,the shape of the crystal grain and the stress in the film.