Abstract: In this study two-dimensional electrophoresis was applied to analyze the difference expression of plasma protein between preperinatal and postperinatal cows. The Hot-SDS method, pH 4-pH7 IPG strips(17 cm)and gradient gel were used for dairy cow plasma proteome analysis. Totally, 239 protein spots were detected using silver staining by PDQuest 6.0, which appeared repeatedly in three gels of each sample.12 spots showed more than 3 fold changes in abundance in plasma protein of cow. Plasma albumin and Haptoglobin were identified by MADILTOF/TOF.Their expressions were increased in the plasma of post-perinatal cow. Haptoglobin content ircreased in postperinatal cow plasma in this study, which showed the physiological changes of the postpartum cows.