The purpose of the present empirical research was to investigate the effects of peer assessment on students’ oral presentation of short stories. With the attempt to investigate the effectiveness of peer feedback, a quantitative research study was conducted. The participants were selected randomly from groups of an 8-group class taking 'Oral Reproduction of Short Stories Course' at the University of Mazandaran. Students' interactions were recorded fully in research groups so that the transcription could be used for the analysis of the data. To be able to decide whether there were any changes in student' oral performance after the treatment, they participated in a pretest at the beginning of the term and a posttest at the end of the term and the results were subjected to paired sample T-test analysis in order to investigate the changes, if any. By analyzing the data, it was observed that the students were mainly concerned with giving feedback on gestures, eye contact, tone of voice and sometimes pronunciation. Grammatical and lexical errors seemed to be fewer than other types by peers. However, an analysis of their written feedback in the form of a checklist showed that they did think there were some inadequacies but refused to say so orally. In the comparison of the pre and posttest results, significant changes were observed after the treatment, and the P value was (sig = 0.03) which meant that there was a significant difference between students’ pre- and posttest performance.