The variations of hardness and electrical conductivity of a deformed supersaturated Cu-Cr alloy have been investigated during isothermal aging. The influence of trace rare earth elements (La, Y or Nd) as a second alloying element was also studied. The results showed that the heavily deformed alloys exhibited an instant increase in both hardness and electrical conductivity due to an accelerated precipitation after a short aging treatment. Compared with the solution treated Cu-0.8wt %Cr-0.05wt. %La and Cu-0.8wt %Cr-0.05wt. %Y alloy, the as-cast Cu-0.8 wt. %Cr-0.05 wt. %Nd exhibited a retarded recrystallization which should be attributed to the pinning effect of primary Cr precipitates lying in the grain boundaries. Rare earth elements can act as a useful second alloying element to inhibit recrystallization of the deformed alloys due to the occurrence of some copper-rare earth intermetallic compounds and rare earth oxides.