Electrical resistivity of Co48Fe25Si4B19Nb4 amorphous alloy and with small additions of rare-earth metals (R = Nd, Sm, Tb, Yb) was studied using the AC four-probe method. It was found that these alloys have a specific behavior of electrical resistivity after crystallization - temperature dependences of resistivity at cooling are non-linear and can be fitted as lnR ~ T-1/4.