Background: Perceived health in caregivers is related to caregiver burden, psychological well‐being and social support. Women perceive poorer health and are more likely than men to experience caregiver overload. Objectives: The objectives of this study were to analyse perceived health, perceived social support and caregiver overload in family caregivers of patients with Alzheimer's disease, as well as to study the effect of the perceived social support as a mediating variable between perceived health and caregiver overload was also analysed, taking into account the caregivers’ gender. Methods: A cross‐sectional descriptive design was used. The sample consisted of 255 family caregivers of individuals with Alzheimer's disease in the Almería Health District (Spain). This study was conducted from January to December 2015. The caregivers’ mean age was 55.35 years (SD = 12.35), with 85.5% (n = 218) being women and 14.5% (n = 37) being men. The following questionnaires were administered: Goldberg's General Health Questionnaire‐28; the Caregiver Strain Index, measuring caregiver overload; and the Duke‐UNC‐11 functional social support questionnaire. Results: Poor perceived health, high caregiver overload and high perceived social support were found. Differences in perceived health and perceived social support were significantly higher in women than in men. In women, perceived social support was a mediating variable between perceived health and family caregiver overload. This mediation was not observed in men. Conclusion: This study suggests that perceived social support influences the emotional well‐being and the caregiver overload of family caregivers of patients with Alzheimer's. However, its effect differs according to gender. It would, therefore, be necessary to have an in‐depth understanding of the variables determining these differences in family caregivers.