The present study aimed at investigating the effectiveness of using the discussion method to improve second year preparatory stage students' writing skills. The participants were 24 second-year preparatory stage students who were randomly chosen. They were taught through using the discussion method. The study employed the quasi-experimental design of one group which was tested before and after the treatment. The instrument of the study included a writing performance pre-posttest. The results of the present study showed that the students of the treatment group performed much better on the post testing. The discussion method was proved to be effective in improving second year preparatory stage students' writing skills.