This paper focuses on the peer written comments in peer review on the basis of constructivism and the interpersonal function in discourse analysis. It is aimed at analyzing the potential autonomous learning capability in the students, the correlation between the students’ English proficiency and their language choice in producing the comments, the contents and manifestation of the interpersonal function in the products as well as the students’ attitudes toward peer evaluation. This study will be beneficial for the improvement of the teaching approach to college English writing and the enhancement of the students’ writing ability.