Abstract: The conceptual evolution from "government affairs information" to "public data" reflects the deep integration of national strategic priorities and digital governance principles, providing a systematic analytical framework for understanding government data governance. This paper aims to systematically trace the evolution of government data governance in China from the perspective of conceptual evolution. It analyzes the ideological transformations, institutional innovations, and practical pathways underlying the shift from "government affairs information" to "public data", revealing the evolutionary logic and driving mechanisms, and deepening the understanding of government data governance development patterns. The study also provides theoretical references for the improvement of governance systems. By combining historical analysis with policy document review, the evolution of government data governance in China is divided into four stages: "government affairs information resource management" (2014 and earlier), "government data openness" (2015–2019), "data element governance" (2020–2022), and "authorized operation of public data and realization of public value" (2023–present). The characteristics, policy foundations, and academic discussions of each stage are systematically compared and summarized across five dimensions: subject scope, data form, attribute cognition, governance mode, and governance objectives. The findings indicate that government data governance in China has undergone a profound transformation from a government internal management orientation to a social public value orientation. Specifically, the subject scope has expanded from administrative agencies to public management and service institutions; the data form has shifted from document-based "information" to machine-readable "raw data"; attribute cognition has evolved from "resource" to "element" to "asset"; the governance mode has progressed from internal sharing to openness and authorized operation; and governance objectives have shifted from enhancing administrative efficiency to driving economic growth and social innovation. In the future, government data governance is expected to move towards multi-stakeholder co-governance, strengthen the realization of public value, and facilitate data circulation while ensuring security and privacy protection.