It is estimated that between 16% and 38% of all elder abusers have a history of mental illness, with most such persons likely having serious mental illness (SMI). Despite the disproportionality of elder abuse perpetrated by persons with SMI, elder abuse and mental health researchers have failed to examine factors associated with the occurrence of elder abuse perpetrated by persons with SMI. By integrating research findings regarding perpetration of community and family violence by persons with SMI and elder abuse perpetrated by persons regardless of their mental health status, this article proposes a preliminary conceptual social–ecological model to explain the occurrence of physical elder abuse perpetrated by persons with SMI. It is intended for this model to further stimulate and guide research in this area. It is imperative that research be conducted regarding factors associated with the perpetration of physical elder abuse by persons with SMI as it is a prerequisite for the creation of practice and policy interventions aimed at preventing and intervening in elder abuse perpetrated by this population.