Resistivity measurements were carried out on Cu-Ge (0.86, 2.41, 4.41, 7.02, 8.68 at%) solid solution alloys, especially containing 4.41, 7.02, 8.68, at%Ge. The results were compared with those for Cu-Al (10.37 at%) and Cu-Ni (20.77 at%) solid solution alloys.Concentration dependence of the resistivity in Cu-Ge alloys has an anomality between 4.41 and 7.02 at%Ge. The change of internal microstructures in the Cu-Ge alloys is recognized from the temperature dependence curves that the first fold points on the curve are at 800°C in 7.02 at%Ge and 8.68 at%Ge, and at 650°C in 4.41 at%Ge solid solution alloy.Isochronal annealing curves of quenched Cu-Ge, Cu-Al, Cu-Ni alloys show that 7.02 at% and 8.68 at%Ge alloys are similar to the Cu-10.37 at%Al alloy in resistivity change and that Cu-4.41 at%Ge alloy is similar to the Cu-20.77 at%Ni alloy. It is considered that some short range order is formed in 7.02 and 8.68 at%Ge alloys.Decreasing of the resistivity is caused by quenching Cu-8.68 at%Ge alloy from 100°∼170°C. It seems that at these temperatures the short range order zones which are formed during slow cooling grow to some extent whereby effective electron scattering centers are formed.