Abstract Giving feedback on second language (L2) writing is a challenging task. This research proposed an interactive environment for error correction and corrective feedback. First, we developed an online corrective feedback and error analysis system called Online Annotator for EFL Writing . The system consisted of five facilities: Document Maker, Annotation Editor, Composer, Error Analyzer, and Viewer. With this system, teachers can mark error corrections on online documents and students can receive corrective feedback accordingly. The system also classifies and displays error types based on user query. Second, an experiment was conducted to evaluate the effectiveness of this system. Fifty EFL (English as a Foreign Language) college freshmen were randomly assigned to two groups. The experimental group received corrective feedback with the developed system whereas the control group used the paper-based error correction method. After the treatment, students in both groups conducted corrective feedback activities by correcting the same document written by an EFL student. The experimental results were encouraging in that the analysis of students’ corrective feedback revealed significantly better performance in the experimental group on recognizing writing errors. Implications for further research are discussed.