As the core element of the digital economy, differences in data governance rules have become a key variable reshaping the global trade landscape. By conducting an in-depth analysis of the internal logic behind the data governance policies of the three major economies—the United States, the European Union and China—this paper draws the following findings: the United States drives global expansion with efficiency as a priority, the European Union builds a defensive system through rule export, and China explores classified and hierarchical governance amid the dynamic balance between security and development. Policy heterogeneity not only gives rise to new type digital trade barriers, but also drives the fragmentation of global rules and restructures the value chain layout of multinational enterprises. Based on this, China should establish a proactive, leading mindset for rule-making, improve the classified and hierarchical cross-border data flow management system, empower the real economy with data, and build a digital trade ecosystem that connects domestic and international markets, so as to achieve a strategic leap from a follower to a shaper in the international rule game.