本研究旨在探究1980～2020年國際師資培育研究的知識結構與趨勢，運用文獻計量法，分析高頻率出現作者、文獻知識聚類及突現詞探尋研究趨勢，以瞭解師資培育研究在不同時間序列中所關注的熱點，描繪40年來師資培育研究在政策、制度與實務的變革及挑戰，並展望未來研究趨勢。本研究採用VOSviewer和CiteSpace文獻計量工具，從Web of Science資料庫中選取1,779篇師資培育研究期刊論文，分析結果共有五聚類：教學實踐與反思、師資培育學程設計、教師信念與質性研究、教師知識與自我效能、教師認同。除此之外，師資培育研究趨勢為：一、巨觀層次的師資培育政策發展研究，由研究政策對師資培育的影響，逐漸轉為落實教育公平與社會正義之探討；二、中程層次的培養機構，轉變為與學校合作培養師資生，再擴及到情境脈絡對師資培育過程之影響分析；三、微觀層次的師資生學習，則從關注師資生在行動中反思以獲得知識與技能，逐步擴展至師資生學習成為教師中各面向的改變。最後，本研究提出師資培育研究未來展望，包括有效的師資培育政策、系統設計師資培育、師資生學習，以供參考。

1. Context and Research Questions Trends in teacher education research reflect changes in policies, systems, and practices as well as the challenges and strategies involved in addressing them. A thorough understanding of these trends is required to propose effective changes to policies and systems and improve teacher education practices (Darling-Hammond, 2016). However, a thorough review of the relevant literature is necessary to determine the factors influencing these trends. To identify issues and knowledge structures in teacher education and examine how these issues are studied, analyzed, and interpreted, researchers must understand how trends in teacher education research have shifted over time and how these trends have influenced teacher education practices. Therefore, we used bibliometric tools to explore the past, present, and future of teacher education research as well as the knowledge clusters and trends in international research on teacher education that are hidden in co-occurrences and burst terms. 2. Literature Review 2.1 Research Scope We examined teacher education during the preservice and induction periods. The terms preservice teacher, teacher student, prospective teacher, and teacher candidate are used to denote individuals that have not yet become regular (in-service) teachers and were the key terms searched for in this study. 2.2 Approaches to Teacher Education Research Teacher education research is greatly influenced by political and professional developments; thus, contemporary historical and political contexts, the positioning of teacher education, definitions of teacher education issues, and research methods influence the body of research (Cochran-Smith & Fries, 2005). Teacher education research considers both the teaching profession and policy implications (Darling-Hammond, 2016). Research on the teaching profession considers the knowledge and competencies of effective teaching strategies for school education, and various theoretical perspectives (e.g., teacher belief, teacher identity) have been used to explore the influencing factors of preservice teachers’ learning experiences (Cochran-Smith, 2016; Popkewitz et al., 1979). 2.3 Types of Teacher Education Research Frameworks Teacher education research has been categorized into handbooks and literature reviews. Both have their own characteristics, advantages, and limitations. For example, teacher education research handbooks are limited by the editors’ judgments and choices of the author or editor. Moreover, they primarily discuss current issues and are thus not wholly reflective of the overarching knowledge structure of teacher education research. By contrast, literature reviews often collect and analyze literature on the basis of a specific perspective or concept but lost others (Houston, 2008). The evolution of perspectives, methodologies, and approaches has increased the discourse and diversity within teacher education research (Cochran-Smith & Fries, 2005; Shulman, 1986). 3. Methods To investigated development of teacher education research, academic articles from 1980 to 2020 that double-blind peer reviews were retrieved from the Web of Science. After filtering for relevance, 1,779 articles were shortlisted. Next, the bibliometric tools, VOSviewer and CiteSpace, were used to understand the focus of teacher education research during different periods, to describe the changes and challenges of teacher education policies, systems, and practices over the past 40 years, and to identify future research trends. 4. Results and Discussion We identified five clusters of teacher education research: teaching practice and reflection, teacher education program design, teacher beliefs and qualitative research, teacher knowledge and self-efficacy, and teacher identity. By analyzing keywords and burst terms, we discovered 44 burst terms that evolved over time. In addition, the research hotspots have varied over the past 40 years, with each trend lasting only a short period. During 1980-2010, teacher education research was dominated by teacher education policy, including training and reform. After 2010, the focus of research alternated between teaching practices and noncognitive learning. Between 2015 and 2020, mathematics, content knowledge, and pedagogical content knowledge were the focus of research, indicating the importance of teacher knowledge and mathematics. Finally, through the literature review and a big data analysis, we discovered the following trends in teacher education research: (1) At the macro level, the focus of teacher training policies has gradually shifted from teacher education to the implementation of educational equity and social justice. (2) On a more specific level, the how institutions cooperate with schools for teacher education and how they analyze the impacts of certain contexts on teacher education process have changed. (3) On the micro level, teacher education has been gradually extended to include changes in various aspects of preservice teachers’ learning. 5. Suggestions Research on teacher education policy is based on multiple standpoints—and in some cases, opposition. Future policy research should employ empirical, scientific evidence to improve policy and debate the effectiveness of teacher education. Teacher education research is deeply influenced by political, social, and cultural factors and should be conducted by teams that test, collect, and analyze data on preservice teachers’ learning environments to identify influential contextual factors. By so doing, a strong foundation can be established for the systematic design of teacher education programs and acquisition of supporting resources. The cognitive and noncognitive learning of preservice teachers is influenced by their personalities and preparation. How changes occur and how preservice teachers can be internally motivated should continue to be explored. Going forward, researchers should consider philosophical, historical, and sociological insights to assess global developments and identify new research goals by reflecting on the academic discourse with peers and across boundaries.