Almost one-fourth of maltreated adolescents report they have thought about killing themselves in the last two weeks. We draw on Agnew's strain theory to develop a model to account for variability in suicidal thoughts among this high-risk group. We used data from a nationally representative sample of 572 maltreated adolescents, aged 11-15. One dimension of relational strain (poorer relationship with peers) and greater depressed mood were directly related to whether adolescents did or did not think about suicide. Depressed mood mediated the relationship between two strain variables (relationship with caregiver and with school) and suicidal thoughts. Child maltreatment strain (being severely harmed) and substance use were not directly related to suicidal thoughts; however, depressed mood appeared to mediate the relationship between drug use and suicidal thoughts. Adolescents who experience child maltreatment and who appear to be disconnected from caregivers, friends and school should be screened for depression and suicidal thoughts.