Social media can lead to rejection, cyber-bullying victimisation, and cyber-aggression, and these experiences are not fully understood as experienced by autistic adults. To investigate this, 78 autistic adults completed self-report measures of social media use, cyber-bullying victimisation, cyber-aggression, and self-esteem. High levels of social media use were found to be associated with an increased risk of cyber-victimisation; whereas self-esteem was positively correlated with feelings of belonging to an online community and negatively correlated with feelings of being ignored on social network sites and chat rooms. Future studies are needed to further investigate the experience of cyber-bullying victimisation of autistic adults.