Research comparing written and audio feedback from feedback analysis and students' perspectives showed the effectiveness of audio feedback in learning writing. Yet, there is a rarity of research on the impact of written and audio feedback in students' performance in writing. Therefore, the present study aimed to compare between teacher written and audio feedback in terms of its impact on students' performance in argumentative writing and students' perception of feedback. The results of this experimental study obtained from the scores of undergraduates in argumentative essays revealed that the experimental/audio feedback group of students (n.40) outperformed the control/written feedback group (n.40) in argumentative writing, which implies that audio feedback was more effective than written feedback in enhancing students' writing. Moreover, the results of the students' responses to the survey and their comments on the open questions showed that students perceived both types of feedback equally satisfactory and accessible. However, while audio feedback was more efficient in details, clarifications and personalization, written feedback was perceived clearer and easier to understand and interpret.