Serum protein and immunoglobulin G (IgG) levels were measured from 16 healthy mouflons (Ovis orientalis musimon) and from 28 roe deer (Capreolus capreolus) in French and Catalonian populations. Electrophoretic patterns were described for each species. The only significant gender-related difference was increased beta-globulins in French roe deer males. Significantly increased alpha1-globulin levels and decreased IgG levels occurred in the young Catalonian roe deer compared with adults from the same group. Values for total proteins, beta-globulins, gamma-globulin, and IgG were significantly higher in the French roe deer, while albumin and albumin/globulin ratio were higher in the Catalonian roe deer. Both populations had the same relative migration distances of the various protein fractions of the electrophoresis.