Background: In China, family caregivers play a major role in caring for people living with Alzheimer's disease (PLWAD), but little is known about the burden this creates. Objective: This study aimed to investigate the burden among family caregivers of PLWAD and the factors influenced it. Methods: Family caregivers of PLWAD were recruited from a hospital in China from January 2018 to July 2018. All data were collected online using the Chinese version of the Zarit Burden Interview (ZBI), and the participants' sociodemographic and caregiving details were obtained. T-tests and Kruskal-Wallis H (K) tests were used to compare ZBI scores between groups. Factors related to the caregiver psychological burden were analyzed using multiple linear regression analysis. Results: A total of 300 participants were assessed, of which 213 (71.00%) were female. More than half of the caregivers were the patient's daughter (51.0%, n = 153). The average ZBI score of the caregivers was 43.05 (13.42). The level of burden was influenced by age, the relationship of the caregiver to the patient, the severity of AD, the caregiver's retirement status, the income level of the caregiver, and the caring time. Regression analysis showed that retired caregivers were more likely to have higher levels of burden and that burden increased with AD severity. Conclusion: Most family caregivers of PLWAD have a considerable caregiver psychological burden. The findings increase the understanding of factors that influence family caregiver burden, and pave the way for potential interventions, such as social support and caregiver empowerment, to reduce their burden.