Background: Chronic diseases in childhood can affect the physical and mental health of patients and their families. Objectives: The objective of this study was to identify the sociodemographic and psychosocial factors that predict resilience in family caregivers of children with cancer and to define whether there are differences in the levels of resilience derived from these sociodemographic variables. Methods: Three hundred and thirty family caregivers of children with cancer, with an average age of 32.6 years were interviewed. The caregivers responded to a battery of tests that included a questionnaire of sociodemographic variables, the Measuring Scale of Resilience, the Beck Depression Inventory, the Inventory of Quality of Life, the Beck Anxiety Inventory, an interview of caregiver burden and the World Health Organization Well-Being Index. Results: The main findings indicate that family caregivers of children with cancer reported high levels of resilience, which were associated positively with quality of life, psychological well-being and years of study and associated negatively with depression, anxiety and caregiver burden. The variables that predicted resilience in families of children with cancer were quality of life, psychological well-being, depression and number of children. Family caregivers who were married and Catholic showed higher resilience scores. We conclude that being a caregiver in a family with children with cancer is associated with symptoms of anxiety and with depressive episodes. Conclusions: These issues can be overcome through family strength, well-being, quality of life and positive adaptation processes and mobilization of family resources.