With the rapid development of digital trade, the importance of cross-border data flow has become increasingly apparent. At present, due to the different digital forms of different economies, the cross-border data flow regulations implemented differ greatly. The governance of cross-border data flow is still a patchwork of regional regulatory policies of various countries, which can’t meet the requirements of the rapid development of digital trade. To form a consistent, coherent and enforceable international governance system for data flows is becoming a new topic of concern for global trade policymakers. In this regard, this paper examines the background of digital trade development and studies the definition criteria of cross-border data flow. Through the international comparison of the current cross-border data flow regulation, the consensus on building an international data governance system is discussed, and the basic framework and key issues included in it are analyzed. Finally, this paper discusses China's role and how to take measures in the international data governance system as a major digital economy developing country, so as to provide inspiration for China to participate in global digital trade cooperation with high quality.