Ostracism is known to result in a range of negative psychological consequences for those who perceive they have been socially excluded. Given the importance of social inclusion and belonging to academic and psychosocial success and good mental health at university, the present study aimed to examine the strongest predictor of perceived university student ostracism from theoretically relevant variables (rejection sensitivity, attachment orientation, social anxiety, and self-esteem) across the literature on social exclusion. A cross-sectional correlation design was employed with university students (N =127). Contrary to expectations, in a multiple linear regression it was found that the only significant predictor of perceived student ostracism was attachment avoidance. The findings underscore the importance of further investigating the psychological precursors of perceived ostracism in students, particularly given that seemingly theoretically important individual difference variables such as rejection sensitivity and social anxiety did not predict perceived student ostracism in our sample. We suggest it is crucial that higher education institutions continue to foster socially inclusive academic environments, particularly for students with avoidant attachment styles.