Although story mapping strategy has been shown to be beneficial in many reading comprehension classes, the benefits of this technique have not been thoroughly investigated in L2 writing research. The small number of previous studies (e.g., Li, 2007; Brunner, 2010) have found the potential benefits of using story mapping strategy on students’ writing performance, but they did not focus on different aspects of students’ writing. Therefore, this study aimed at investigating the effect of story mapping strategy on writing performance of EFL learners in terms of writing components (i.e., organization, content, grammar, mechanics, and style). After administering a standard proficiency test (OPT), 30 out of a pile of 82 Iranian EFL learners all majoring English teaching were selected and assigned to two groups: one experimental group and one control group. Both experimental and control groups completed two thirty-minute composition writing tests, one as a pre-test and the other one as a post-test. The experimental group received four sessions of instruction on how to use story mapping strategy in writing personal narratives. The results of One-way ANOVA and post-hoc Scheffé test indicated that the experimental group, which used story mapping strategy, made more progress in their personal narrative writings. Also, the results revealed that L2 learners made more progress in all writing aspects. The study contributes to teaching pedagogy by encouraging teachers to use story mapping strategy in L2 writing classes
