Abstract: Affected by many factors such as information technology challenges, multiple value conflicts, and the interaction between domestic and foreign rules, extraterritoriality of data protection law has become a legal issue that China must take seriously. At present, the international community mainly expands the scope of application of domestic data rules through legislative and judicial approaches. Among them, the judicial path fills in to a certain extent the lack of traditional data legislation on the issue of extraterritorial effectiveness, but it has certain limitations. Especially when the domestic data protection policy has obvious expansion needs, it is necessary for legislation to directly declare the issue of extraterritorial effectiveness. Intuitively, although the scope of application of data legislation depends on the independent choice of a country ’s sovereignty, the determination of extraterritoriality of data protection law still needs to be reviewed at the level of international law if all considerations are made. Taking into account China's data protection policy and the need to participate in global data governance, China should establish extra-territorial effectiveness clauses in legislation, and set the scope of application of the data protection law by utilizing established institution standards and effect criterion. In the implementation stage, the role of the court in applying the extraterritorial effectiveness rules should be strengthened, and the court should be supported to explain the scope of the effectiveness of China ’s data protection legislation based on the facts of individual cases, so as to form a benign interaction with the legislative and administrative authorities and promote the data governance system Construct.