This paper presents a scientometric analysis of international studies on academic English writing from 1990 to 2015 with the tool CiteSpace III. The research data (i.e., 2176 research papers) were retrieved from the core collection of Web of Science-SSCI. The core references, the developmental route and the research frontier of academic writing studies were visualized through the networks of co-cited references and the summary table of references with high co-cited frequency and strong betweenness centrality. The main research findings include: 1) the top 3 high-impact references in academic writing research are Swales (1990), Biber et al. (1999), and Hyland (2000); 2) the top 3 references representing pivotal transforming points in this area are Ivanic (1998), Berkenkotter & Huckin (1995), and Myers (1989); and 3) the key research-front terms of this area are cultural differences, feedback, lexical bundles, and international publishing.