To obtain practical magnetooptical materials having large Kerr rotation Θk, high perpendicular coercivity Hc and relatively low Curie temperature Tc( <tex xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">\sim200\deg</tex> C), rare-earth elements having a one-ion anisotropy were added to Gd-Fe-Co amorphous alloy system, which has a large intrinsic Kerr rotation but an in-plain anisotropy. As a result, replacing Gd by Tb,Dy,Ho, a large perpendicular anisotropy Ku is induced associating with the increase of Hc. With the optimization of their compositions, Gd-R-Fe-Co (R=Tb,Dy,Ho) amorphous films with Θk= 0.42-0.45° (at the wavelength of 822nm), Tc <tex xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">\sim200\deg</tex> C, and Hc=160-400 kA/m(2-5 kOe) were obtained.