The present was carried out to find out relation between introversion/Extraversion with academic Achievement among male high school students. A sample of 50 students were selected randomly for the present study. MPI (Mandsley personality inventory) Hindi version of Eyserick IEPI prepared by S.Jalota and S.D. Kapoor was used for the the study. The findings revealed that there is perfect positive co-relation between introversion and academic achievement that is if one varies another will also varies on the other side there is negative correlation between extroversion and the academic achievement that is if one increases other will increases. It may be permitted that introvertswill show better performance in educational tasks, and then the extroverts, Introverts do better at school and achieve high university grades. This setting of higher goal for prolonged period of time is essential in any long term programme of academic achievement.