In this paper, fundamental rationale for setting up performance criteria is discussed and based on which an index scheme of evaluation is envisaged for use on evaluating performance of various major stake holders in the open electricity market environment. Special reference will be made to the China's stated objective of reform in the electricity supply industry as to enhance the utilities performance and to build a fair and practicable power market mechanism. The proposed index scheme is in good time to help identify the basic criteria for evaluating the industry's performance in social, technical and economic aspects