Based on conversation analysis theory, this study explored how teachers and students used discourse markers in foreign language classrooms and how these markers affect classroom interaction. The results showed that teachers use different discourse markers in different teaching stages such as lead-in, presentation, practice and summary to make their teaching more organized and clearer. However, students used these markers less often, and their expressions are often less coherent. Based on these findings, the study suggests teaching strategies for teachers and learning strategies for students to improve how they use discourse markers. This can help make foreign language teaching more effective and interactive.