Academic peer mentoring program between peer mentors and mentees has been widely implemented by school counselors. However, few researches have been examined the outcome of the Peer Mentor Module (PMM) on mathematics grade achievement in school. The PMM aim to improve the peer mentor’s soft skills namely in interpersonal relationship, communication, motivation, empathy and emotional stability. The present study examines the effect of participation of form four students in a secondary school in academic peer mentoring program as well as differences between individual and group approach on mathematic grade achievement. A total of 45 sampel form four students who failed in mathematic monthly tests whereby 30 students as mentee served as treatment group while the remainder 15 students as a control group. All 20 peer mentor students participated in an eight hours workshop using the Peer Mentor Module. The subjects were examined at week one for pre-test and post-test at week eight. Data were analyzed using frequency, percentage and mean, with inferential analysis using Mann-Whitney U tests. Statistical analysis included (group x time) measures t-test to determine between and within group mean differences. The finding supports the hypothesis that PMM intervention shows positive effects on increasing the mathematic grade. It was found that the mathematic grade of Individual Peer Mentor Treatment Group is higher than the Group Peer Mentor Treatment Group. Therefore, a one-on-one session (one peer mentor and one mentee) provide better individualized attention for students as well as establish understanding of the content and advices from a peer mentor. This approach can become an important aspect in implementing the guidance and counselling practice that focus in academic peer mentoring.