The spin‐polarized electronic structures of Gd18Co82and Gd32Co68amorphous alloys are calculated self‐consistently in order to study their magnetic properties. The calculated electronic‐state densities of the Gd and Codstates do not have well‐resolved peaks; this is a characteristic of amorphous alloys. The magnetic moments of Co and Gd are 1.51 and 7.16 &mgr;Bin Gd18Co82, and 1.38 and 7.14 &mgr;Bin Gd32Co68, respectively. These values show good agreement with experimental data. The exchange splitting of Codstates in Gd32Co68is smaller than in Gd18Co82, while the density of states at the Fermi level in the former is higher than that in the latter.