The main purpose of the present study was to examine the relationships between HEXACO personality traits and rolefulness. Data were collected from 96 Japanese university students. The results showed that honesty–humility was negatively associated with social rolefulness, and extraversion and openness were related to increased social rolefulness. In addition, openness to experience and emotionality were associated with increased internal rolefulness. This model revealed significant relationships between personality traits and rolefulness, contributing to the understanding of how rolefulness develops based on individual characteristics.