Background: Parents of persons with severe mental illness (SMI) often experience burden due to the illness of their daughter or son. In the present study, the possibility that parents' self-stigma moderates the relationship between the parents' insight into a daughter's or son's illness and the parents' sense of burden was investigated. Methods: Levels of insight into a daughter's or son's mental illness, parent self-stigma, and parent burden of 127 parents of persons with an SMI were assessed. Regression analysis was used to test the putative moderating role of parents' self-stigma. Results: Self-stigma was found to mediate rather than moderate the relationship between insight and burden. Accordingly, parent insight into the mental illness of a daughter or son appears to increase parent burden because it increases parent self-stigma. Conclusions: The implications of these findings for practice, theory, and future research are discussed.