Objective. To investigate the association between wellness and sociodemographic characteristics of caregivers of people with cancer. Methods. This was a cross-sectional study conducted in Maringá, Paraná, Brazil, with 96 caregivers. Data were collected between July 2011 and February 2012. A global wellness assessment scale was used to measure wellness and data on sociodemographic characteristics were gathered using a complementary form. Results. The characteristics associated with reduced wellness among caregivers of people with cancer were: being separated, being a mother, having a higher education degree, being employed, being the sole caregiver, having a family income of up to one minimum wage and presenting health problems. Conclusion. Some demographic characteristics are associated with loss of wellness among these caregivers. Nurses must take this information into account when formulating strategies to improve the wellness of caregivers, considering their context.