Pregnancy toxemia is a metabolic disease of pregnant ewes which causes significant economic losses in sheep industry. The pathophysiology and metabolic changes of this disorder remain poorly understood. We conducted this study to describe the serum protein pattern associated with the pregnancy toxemia in ewes. In this study, the electrophoretic pattern of serum proteins of 15 ewes with naturally occuring pregnancy toxemia and 12 ewes with uncomplicated pregnant were investigated by Sodium Dodecyl Sulfate Polyacrylamide Gel Electrophoresis (SDS-PAGE). Serum protein patterns were mainly characterized by four bands and located in the 76 kDa, 66 kDa, 55 kDa and 29 kDa both diseased and control groups. The percent of the 66 kDa, 55 kDa and 29 kDa proteins were decreased (P < 0.001 for 66 kDa; P < 0.01 for 55 kDa and P < 0.05 for 29 kDa) while 76 kDa (P < 0.05) protein was significantly increased (P < 0.001) in ewes with pregnancy toxemia relative to controls. Positive correlations were found between activities of liver enzymes and percentage of the distribution in 76 kDa, 55 kDa proteins. In contrast, there was a negative correlation between the 66 kDa protein and liver enzymes. In conclusion, the results of this study demonstrate that the percentages of the 76 kDa, 66 kDa, 55 kDa and 29 kDa proteins are significantly altered in ewes with pregnancy toxemia. However, further studies are needed to explore the potential role of these alterations in the pathophysiology in ewe with pregnancy toxemia.