Abstract: [Objective] To establish two-dimensional gel electrophoresis methods (2-DE) for sheep serum.[Method]The experimental conditions of 2-DE were optimized,and various extraction and process methods,different pH IPG strips,different concentration of SDS-PAGE were studied.[Result] The results showed that the 10; tca/ acetone precipitation method was used to deal with the serum protein,pH 4-7 IPG,2.5 mg,18 cm,10; sds-page,and a good 2-DE map was obtained.[Conclusion]This study got a good IPG maps for sheep serum protein.We have successfully established a 2-DE technique for sheep serum proteome,which can provide important technical information for evaluation of transgenic sheep biological safety.