In the beginning of new millennium, Business-to-Business(B2B) Electronic Commerce(EC) is a hot issues of the world business and economic communities. The market of B2B EC is increasing rapidly, and become a more complex and competitive because many participants and intermediaries are play on their own objectives and strategies. To cope with the situation, participants of B2B EC market should make play with a competitive strategies. So, the participant enterprises must know the critical success factors of their own EC market. This study identifies B2B EC success factor measurement sets, and explores several success factors based on the perceived importance of B2B EC practitioner in the manufacturing enterprises. The study tests the differences of success factors by IS level, EC business model characteristics, and EC introduction and operating characteristics.