As technology increasingly takes center stage of our lives, there are compelling reasons for incorporating technologies into the classroom. The prevailing of CALL has greatly changed the traditional teaching mode and added new contents into the existing teaching materials. As a significant skill for EFL learners, there are abundant researches in writing, yet little documentation exists on the application of CALL in writing classroom. This paper reviews relevant theories and research, and then investigates three research questions by an empirical study. The results gained have some pedagogical implications in the future.