This paper reports on the result of a study on Chinese university EFL learners' foreign language writing anxiety in terms of general pattern, effect and causes. 1174 first-year students answered the 26-item Foreign Language Writing Anxiety Scale (FLWAS) (Young, 1999) and took an English writing test, 18 of whom were invited for semi-structured interviews. The results showed that 1) FLWAS had three principal components--low confidence in English writing (FLWAS1), dislike of English writing (FLWAS2) and English writing apprehension evaluation (FLWAS3), 2) the whole sample, as well as male and female students, were generally confident in and liked English writing, and were not apprehensive of having their English writing evaluated, 3) significant differences existed between male and females students, and among different proficiency groups in all the FLWAS scales, 4) foreign language writing anxiety significantly negatively affected students' performance in the English writing test, and 5) a number of factors contributed to the students' foreign language writing anxiety.