Peer teaching, which has been widely applied in the university setting, has been reported to assist language learners. However, there have been concerns that such tutoring, which employs a more able learner to assist lower-level ones, may hinder learner autonomy. Nevertheless, little attention has been paid specifically to this issue. With this in mind, this preliminary qualitative study examines whether or not peer teaching can help foster EFL students’ autonomy in isolated grammar learning (focus on forms) at the tertiary level based on the students’ reports. This study is imperative as peer teaching is often implemented in universities and grammar competence is crucial to effective communication. In addition, besides enhancing the acquisition of grammar competence through noticing, explicit knowledge of grammar is necessary for the student’s future careers as English language professionals. A questionnaire and interviews were used to collect data from 29 survey participants and 11 interviewees, all of whom had just taken grammar courses and joined a peer tutoring program. The students’ responses show that peer teaching can promote their learning autonomy. Most students reportedly performed various activities that enhanced autonomous learning during their peer teaching. In addition, the participants also believed that the teaching method assisted them with their ability to plan, monitor, and evaluate their grammar learning. Here, learning motivation, subject understanding, problem-solving skills, as well as monitoring and evaluating skills were reported to have specifically improved from the tutoring. Despite this positive outcome, peer teaching did not seem to improve the autonomy of some students, especially the less able ones, in the areas of knowledge construction, provision of self-study materials, and frequency of grammar self-study.