Personality development depends on lot of factors such as home environment, guardians or parents mutual relationship, sibling’s behavior, health, environment, neighborhood & school environment in which the child lives, in other hand peer pressure would be mould a child or student in a positive or negative direction in behavior. The main aim of the present study was to explore the relationship between personality development and peer pressure of senior secondary school students. Survey method and random sample of students (167 male and 167 female), Peer Pressure scale developed by Sandeep Singh & Sunil Saini and Singh’s Differential Personality Inventory (SDPI) were applied. Independent sample t- test was employed to assess the difference in gender wise peer pressure and Pearson Correlation used for study the relationship between peer pressure and development of personality. Difference in male and female students peer pressure and correlation between peer pressure and development of personality emerged in this study. Very week positive degree correlation was found between peer pressure and development of personality. This study was found male senior secondary students have more peer pressure than female senior secondary students.