With the rapid advancement of speech synthesis technology, synthesized Putonghua has been widely applied in education, news media, public services, and other real-world scenarios. Consequently, increasing attention is being paid to its linguistic normativity and speech quality. Existing speech synthesis evaluations primarily focus on technical performance and do not adequately address the needs of language governance, including the national standards for spoken and written Chinese, and Putonghua proficiency assessment. Drawing on the development practice of the Standards and Guidelines of Synthesized Putonghua Proficiency Assessment, this study builds upon the theoretical and institutional foundations of the Putonghua Proficiency Test (PSC) and examines the core approaches and frameworks for synthesized Putonghua proficiency assessment, particularly in light of the shifts from evaluating human speakers to machines. The study proposes four guiding principles: goal orientation, human-machine alignment, inheritance with innovation, and normativity and scientific validity. Key components discussed include level classification, characteristic descriptors, task design, scoring methods, and experimental validation. This study outlines a structured approach to constructing both assessment standards and assessment design. It argues that synthesized Putonghua proficiency assessment is not simply an expansion of the PSC’s scope; rather, it requires a reconstruction of rating logic, assessment content, and implementation mechanisms in response to changes in assessment objects and represents an important extension of language governance in the era of intelligent speech technologies.