Abstract-Writing as a communicative activity imposes great difficulties on EFL learners and both cognitive and affective aspects of writing have a sharing part in this complex process. The current study aimed to explore the effect of explicit writing strategy instruction, prewriting strategies in particular on reducing writing apprehension, and promoting writing performance.42 intermediate EFL students participated in this study, 28 students in two experimental groups received the treatment and the results compared to their 14 counterparts in the control group. All the participants received Writing Apprehension Test (WAT) as the pretest and posttest. They further were expected to write two expository essays at the beginning and end of the study. After administrating the pretests and posttests, the results reflected on the effectiveness of explicit writing strategy instruction and the potentials of prewriting strategies in alleviating the level of writing apprehension. Further, explicit instruction of prewriting strategies greatly optimized the writing achievement of students in the two experimental groups. The findings of the present study also suggest that the implementation of explicit strategy instruction by the teacher can make a world of difference for students in learning process.