Background Family caregivers of elderly patients with spinal tumours experience considerable pain and burden during the care process. This study aims to investigate the factors associated with caregiver burden in family caregivers of elderly patients with spinal tumours. Methods A total of 220 elderly patients with spinal tumours (age >= 65 years) hospitalized at the spine centre of our hospital from January 2015 to December 2017 and their family caregivers were recruited for this cross-sectional study. All participants completed a sociodemographic questionnaire. Caregiver burden, social support and self-efficacy were assessed by the Chinese version of the Zarit Burden Interview (ZBI), the Social Support Rating Scale (SSRS) and the General Self-Efficacy Scale (GSE), respectively. The factors related to caregiver burden were analysed by multivariate analysis. P < 0.05 was considered statistically significant. Results The 216 elderly patients with spinal tumours were 71.59 +/- 8.49 years old, and their caregivers were 70.46 +/- 9.13 years old. A total of 170 patients were cared for by their spouses, who accounted for 78.7% of all caregivers. The ZBI score for the family caregivers was 35.5 +/- 7.5, and most caregivers (84.5%) reported a moderate or heavy burden. The factors related to caregiver burden included patient paralysis, the primary cancer site, chemotherapy and/or radiation, cognitive dysfunction, functional status, monthly income, pain score, caregivers' SSRS score, and GSE score. Conclusions Most family caregivers of elderly patients with spinal tumours have a considerable caregiver burden. Interventions based on social support and self-efficacy can help reduce caregiver burden.