Objective: To examine the relation between homelessness and suicidality and to test bullying as a mediator and parental support as a moderator of these relations. Background: Youth from low-income families are more likely to be bullied and in turn experience negative mental health outcomes. Parental support has been reported to mitigate the effects of stressful events, such as being bullied. However, these relations are still undocumented among youth experiencing homelessness. Method: This study included a random sample of 2,049 stably housed and 64 homeless youth enrolled in the Delaware Public Schools, grades 9 through 12, who completed the 2015 Delaware Youth Risk Behavior Survey. Hayes's PROCESS macro was used to test for a moderated mediation relation between bullying, suicidality, and parental support for homeless youth. Results: Bullying mediated the relation between homelessness and suicidality, and parental support moderated the relation between bullying and suicidality. Youth experiencing homelessness reported more bullying, which was associated with more severe suicidality. For youth experiencing homelessness with low levels of parental support, bullying was associated with more severe suicidality. Conversely, for youth with high levels of parental support, bullying was not associated with more severe suicidality. Conclusion: This study indicates that bullying is a mechanism through which homelessness and suicidality are related, while also demonstrating the importance of parental support. Implication: The increased risk of suicidality among youth experiencing homelessness who are bullied, as well as the effects of parental support, warrant attention from school personnel and youth service providers.