People differ in how strongly they believe that, in general, one gets what (s)he deserves (i.e., individual differences in the "general belief in a just world"). In this study (N = 588; n = 60 with a formal autism diagnosis), whether or not autistic people and those with high autistic traits have a relatively low general belief in a just world is examined. The results revealed the expected relationship between autism/higher autistic traits and a lower general belief in a just world. In a subsample (n = 388), "personal" belief in a just world, external locus of control, and self-deception mediated this relationship. These findings are discussed in terms of autistic strengths (less biased information processing) and problems (lowered well-being).