Over the past two decades, washback has attracted wide attention from researchers in China and the number of studies on washback has increased considerably. However, it is found through literature review that some researchers have less clear understanding and even misunderstanding of the nature of washback, the factors contributing to washback, dimensions of washback, as well as the relationship between washback and validity. As a result, it reduces the scientificness of research and makes the research results less convincing to some extent. The author suggests that it is necessary to clarify the basic issues of washback studies with the purpose of providing advice for future washback studies.