Foreign language writing is often used in work and daily communication. At the same time, it has a great weight in many important examinations, reflecting the students comprehensive application level of foreign language. Related studies have found that students experience anxiety when writing due to lack of confidence, fear of evaluation, being influenced by local culture, procrastination, and a high level of epistemological beliefs. This will not only inhibit their cognitive activities and affect their writing performance, but also discourage their enthusiasm for learning and hinder the improvement of their writing ability. However, on the contrary, some researchers have found that writing anxiety may also stimulate students to work harder and more efficiently on writing tasks. This paper will review the related studies on writing anxiety in foreign languages, summarize its classification, effects and causes, then find ways to reduce students writing anxiety and improve the level of their writing. Finally, some incompleteness of the current research will be reflected, with a view to providing implications for future research.