The purpose of the present study was to investigate the effect of self-assessment and peer-assessment activities on second language (L2) writing self-regulation of Iranian English-as-a-foreign-language (EFL) learners. For this purpose, a sample of forty-six English major students from two intact classes at an Iranian Islamic Azad University were recruited as the participants of the present study. Then, the two classes were randomly assigned to a self-assessment group (N=22) and a peer-assessment group (N=24). The self-assessment group was instructed on the writing assessment criteria in order to self-assess their writing tasks and the peer-assessment group was trained on how to assess the writings of their peers. The treatment carried out for the self-assessment and peer-assessment groups lasted for a period of one university semester. The data was collected through Second Language Writing Self-regulation (SLWS) administered as the pre-test and post-test of the study. The results obtained from the data analysis indicated that both self-assessment and peer-assessment were conducive in enhancing L2 writing self-regulation of the participants. Nevertheless, further analysis of the data indicated that the participants in the peer-assessment group were better than those in the self-assessment group with regard to writing self-regulation, suggesting that peer-assessment activities were more effective than the self-assessment activities in contributing to enhancing writing self-regulation of the EFL learners. The justification of the findings and their implications for L2 writing pedagogy are also discussed.
