The current study has two research questions: 1) Are EFL students’ ratings comparable with the advanced or native TESOL graduates’ ratings? 2) What are the significant variables that discriminate one self-marked proficiency group from another? To address question 1, 90 Korean EFL learners rated 3 sample essays on a 5-scale with four writing features (organization, content, language use, and holistic feature), Twenty-five TESOL graduates also rated the sample essays given the same scoring rubric. The students’ ratings then were compared to the ratings of TESOL graduates. To address research question 2, 100 students’ responses to 10 survey items were analyzed, using discriminant analysis (DA). The result showed 1) that significant difference were observed in a few analytic features between students’ ratings and colleagues’ ratings, and 2) that the students who marked themselves as high-proficient writers were likely to respond with confidence that their ratings were accurate. In conclusion, differing L2 proficiency level is partly, but not fully associated with rating performance in subjects who are able to read and comprehend English sentences. On the other hand, L2 proficiency influenced student raters’ perception.