Background: Parents of children following a traumatic medical event (TME) are known to be at high risk for developing severe post-traumatic stress symptoms (PTSS). Findings on the negative impact of TMEs on parents’ PTSS have been described in different cultures and societies worldwide. However, in some cases, a specific ethnic group may also be a minority within a given region or a country, contributing to increased risk for parental PTSS following a child’s TME.Objectives: The current study aimed to examine differences in PTSS between Israeli-Arab and Israeli-Jewish mothers, following a child’s TME. More specifically, we aimed to examine the risk and protective factors affecting mother’s PTSS from a biopsychosocial approach.Methods: Data were collected from medical files of children following TMEs, hospitalized in a pediatric rehabilitation department, during the period 2008–2018. The sample included 47 Israeli-Arab mothers and 47 Israeli-Jewish mothers. Mothers completed the psychosocial assessment tool (PAT), the post-traumatic diagnostic scale (PDS).Results: Arab mothers self-reported significantly higher levels of PTSS than their Jewish counterparts. Further, Arab mothers perceived having more social support than Jewish mothers did. Finally, our prediction model indicated that both Arab ethnicity and pre-trauma family problems predicted higher levels of PTSS among mothers of children following TMEs.Conclusions: Focusing on ethnic and cultural effects following a child’s TME may help improve our understanding of the mental health needs of mothers from different minority ethnic groups and aid in developing appropriate health services and targeted interventions for this population.